For Andy Burnham, it has been the summer of his dreams.

He has finally been able to enjoy the fulfilment of his life’s work, having become Labour leader at the third time of asking – and prime minister – on July 20.

Without the inconvenience of having to answer to parliament, which went into recess the week before, Burnham has largely spent his time making a string of announcements and seemingly endless TikTok videos with well known content creators.

In his first week in No.10 alone, the new PM announced a business rate cut for the hospitality sector, a £2 cap on bus fares and scrapping VAT on electricity bills.

There have also been announcements on reviving “hollowed out High Streets” and a crackdown on “rip off discounts and subscription traps”.

Burnham has also been travelling the length and breadth of the country, meeting voters and hammering home the message, if indeed there was any doubt, that his government will do things differently than Keir Starmer’s.

He even managed to squeeze in a visit to the Hill Dickinson Stadium to watch his beloved Everton record a rare Premier League victory.

If you throw in his comprehensive triumph in the Makerfield by-election on June 18, it is little wonder that Burnham has rarely been seen without a smile on his face over the past three months.

He will be well aware, however, that as sure as summer will shortly make way for autumn, his political honeymoon is also coming to an end.

Alex Newton, deputy director of the More in Common think-tank, said Burnham still faces a huge challenge in winning back the voters Labour have lost since the 2024 general election, especially those who have switched to Reform.

Brits are also evenly split on whether the prime minister attempts so far to tackle the cost of living are simply a publicity stunt or a genuine effort to help them, he said.

“Some 54% weren’t confident he will address the cost of living,” Newton told HuffPost UK. “That kind of pessimism means that if he doesn’t deliver on this, it will hit Labour and his approval ratings.”

The prime minister is faced with a lengthy list of other issues, each with the potential to throw his new government off track.

Here, HuffPost UK looks at the various challenges facing the PM as MPs return to Westminster on Tuesday.

On day one, justice secretary Alex Norris will set out how he plans to exempt two of the killers of PC Andrew Harper from the government’s highly controversial early release scheme.

Norris was given that particular hospital pass by Burnham following a huge public backlash to the prospect of Jessie Cole and Albert Blowers walking free after just six years behind bars.

But even if, as expected, Norris does manage to tweak the policy to keep the two men in prison, the sight of other dangerous criminals getting out early will undoubtedly damage the PM’s standing with the public.

The sight of 230 migrants crossing the English Channel on a single boat became one of the defining images of the summer.

Although Home Office statistics showed that the overall number of asylum seekers arriving in the UK is down by 23% compared to a year ago, a YouGov poll showed the public believes the total has actually gone up.

Burnham’s acknowledged the importance of solving the problem by visiting Dover at the start of August, when he vowed to be “relentless” in his attempts to stop the boats.

But it is a problem which has confounded several prime ministers. If Burnham fails as well, Nigel Farage is waiting in the wings to replace him in No.10.

If the first priority of government is to keep its citizens safe, then providing the necessary funds for the military should be its number one priority.

Keir Starmer left behind a £5 billion black hole in the government’s Defence Investment Plan (DIP), which John Healey needs to fill when he delivers his first Budget as chancellor in October.

That is the same John Healey who resigned as Starmer’s defence secretary over the then PM’s failure to commit to spending 3% of gross domestic product (GDP) on the military by 2030.

Despite that, Healey has so far refused to commit to coming up with the cash himself, despite now being in charge of the nation’s purse strings, an apparent U-turn dismissed as “unforgivable” by the Tories.

With the geopolitical situation now more uncertain than at any time since the end of the Cold War, Burnham and Healey simply have no other option than to find the money needed to defend the realm.

The fact that Burnham became Labour leader and PM unchallenged, he remains untested in a number of areas – none more so than on foreign affairs.

Although he has said he wants to be more domestically-focused than his predecessor, he can hardly ignore the ongoing conflicts in Ukraine, Iran and Gaza, this is a situation which can best be described as sub-optimal.

It was significant that he chose Kyiv for his first foreign trip, a clear sign that Burnham will follow the example of Boris Johnson, Rishi Sunak and Starmer in offering Volodymyr Zelenskyy his steadfast support.

The PM even gave the Ukrainians a British blueprint for developing their own long-range missiles – a move which enraged the Kremlin.

On Gaza, Burnham has criticised Starmer for his response to Israel’s bombing campaign in the wake of the Hamas terror attacks on October 7, 2023.

The PM’s future approach to that conflict will be another defining issue of his premiership, with the potential to blow apart the tentative left-of-centre coalition he has been building.

As if wars around the world were not enough to contend with, Burnham must also try to maintain a positive relationship with Donald Trump, something Starmer ultimately failed to do.

The early signs have been positive, with the US president describing the prime minister as “terrific” on the basis of one telephone call on Burnham’s first day in the job.

However, this view seems to be based on the assumption that Burnham will satisfy Trump’s desire to see the North Sea opened up to more drilling for oil and gas.

Although he has vowed to be more “pragmatic” on the issue than Starmer, the PM has also insisted he will stand by Labour’s manifesto commitment not to award new drilling licences.

The pair are due to meet at the UN General Assembly in New York next month.

As unpalatable as it may be for a man who once said Trump was not welcome in Manchester, making nice with the president would give Burnham one less headache to contend with.

September will also see Burnham’s first Labour Party conference as leader, an event which promises to be far more upbeat than a year ago, when it was already apparent that Starmer was not up to the job.

With Labour now topping the polls and imbued with a renewed sense of optimism, the prime minister can expect a hero’s welcome.

It will not all be sweetness and light, however, with left-wing campaign groups determined to pile pressure on Burnham to declare Israel’s actions in Gaza a genocide, and to impose a complete arms embargo on the country.

Doing so would provoke an angry backlash from groups such as Labour Friends of Israel, however, and trigger the kind of party split which the PM is determined to avoid.

Political consultant Laura Emily Dunn told HuffPost UK: “The return to parliament will be a test of the PM and the government’s prioritisation – which of the hot topic issues will they want to deal with first? Early prisoner release? The The economy? Small boats? The devil will be in the detail.”

Senior Labour figures said Burnham should enjoy the Bank Holiday weekend, as it will only get more difficult from now on.

One told HuffPost UK: “Andy came to office making a lot of big promises, and his summer has gone well.

“But that means the party’s expectations are sky high. How will he manage that through Labour conference, the Budget, a spending review process and weekly PMQs sessions?

“Andy promised all sorts and now they are hinting the Budget will be steady. Basically – the runway on promising all things to all men is getting shorter and shorter.”

The source added: “Apart from ‘vibes’, what’s the difference with what Starmer was doing? That’s not to dismiss vibes – they really matter – but politics always comes back to policy in the end.”

A Labour MP added: “I think his main challenge is all the promises Andy made as mayor of Manchester to the membership will need to be kept.

“Any hint he’s reneging on them will pour rocket fuel on the Greens when they’re on the ropes. He’s also got to navigate a restive Parliamentary Labour Party, with some pissed off Starmer loyalists, and he’s got to start delivering for an impatient electorate.

“Basically, Andy’s September 2026 biggest problem is Andy Burnham from March 2026.”

Listen to Commons People, the podcast that makes politics easy. Every week, Kevin Schofield and Kate Nicholson unpack the week’s biggest stories to keep you informed. Join us for straightforward analysis of what’s going on at Westminster.

Andy Burnham has claimed his devolution plans strengthen his case for a written constitution for the UK.

The prime minister said the UK’s “antiquated” political system needs reform if equal opportunities are to be effectively shared out across the country.

Britain is one of the only major democracies without a codified arrangement which lays out how the country should be governed.

The UK’s constitution is currently established through history by common law, statutes and conventions.

Burnham has already decided to allow regional mayors to keep a proportion of income tax to spend on their local area by early 2028.

He has also set up No.10 North, an alternative to 10 Downing Street in the north of England, to symbolise his commitment to moving power out of Westminster.

He said his devolution plans “increase the case for a constitution because Britain is changing through this, England is certainly changing through this.”

He claimed the country needs to set up a codified model of devolution which works for Wales, Scotland, Northern Ireland and England.

“In the end, I think it does start to point towards a new constitutional settlement… with that commitment to equivalent living standards,” he said.

He added that his promise to implement “good growth in every postcode” was “more than just a sound bite”.

The prime minister did not outline any time frame for implementing such a historic change.

Countries usually adopt a written constitution following major events like revolution or war, when governments need to signal a departure from previous regimes.

The prime minister first floated the idea in his 2024 book Head North, co-written with Liverpool city region mayor Steve Rotherham.

He said deep inequality had become part of Britain because it had not moved on from the “feudal state” which held power in Westminster.

“Our failure fully to set out the rules for how the country should be run is one of the principal reasons why Britain is one of the most unequal major countries in the world,” he wrote.

“Our unwritten and murky constitutional arrangements have had the effect of hoarding power in a small number of hands – in Whitehall and Westminster and, by extension, in the powerful networks of institutions and vested interests that surround them.”.

Listen to Commons People, the podcast that makes politics easy. Every week, Kevin Schofield and Kate Nicholson unpack the week’s biggest stories to keep you informed. Join us for straightforward analysis of what’s going on at Westminster.