Donald Trump’s former vice-president has slammed his decision to waive sanctions against Russia as the war in Ukraine goes on.

Mike Pence said the move “is decidedly not in the national interests of the United States and should be reversed”.

The US Senate passed the Lindsey O. Graham Sanctioning Russia and Iran Act last month, and it was then signed into law by Trump himself.

It gave the president the power to impose extensive new tariffs and sanctions on Russia and countries that buy energy products and other critical exports from the country as its war on Ukraine continues.

But Trump announced he was blocking the new sanctions just two days before they were due to come into force.

In a post on X, Pence – who has become a fierce critic of Trump – condemned the move.

He said: “President Trump’s decision to waive sanctions against Russia as Putin continues his brutal war of aggression against Ukraine dishonors the legacy of the late Senator Lindsey Graham and is decidedly not in the national interests of the United States and should be reversed.

“Putin is a war criminal and only understands strength. Waiving Graham Act sanctions on Russia signals weakness at a moment that demands American strength.

“Now is the time to stand strong against Russian aggression, just as we did during the years of the first Trump Administration.”

Pence said that if Ukraine won the war, it “would be a victory for freedom and is squarely in the national interests of the United States”.

He added: “If Putin overruns Ukraine, I have no doubt it will only be a matter of time until Russia’s military crosses a border that our troops will have to deal with him.

“For the cause of freedom, for America’s national security and that of our allies including Ukraine, President Trump should restore sanctions under the Graham Act immediately, rescind the diesel deal with Russia and rally our allies to ensure Ukraine has the military support it needs to repel and defeat this Russian invasion once and for all.”

Trump has faced accusations that he limited Ukraine’s access to the Starshield network which helps to protect the country from Russian attacks.

The president has also called for Ukrainian president Volodymyr Zelenskyy to be replaced while agreeing a sanctions-busting deal with Vladimir Putin to buy Russian diesel.

Critics have said that is a desperate attempt to bring down pump prices for American motorists ahead of next month’s midterm elections, which Trump’s Republican Party is expected to lose heavily.

Former UK foreign secretary Sir Malcolm Rifkind described Trump’s behaviour as “repulsive” and “a disgrace”.

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