David Lammy accused a Reform UK MP of “swallowing conspiracy theories” over a question she asked him in the House of Commons.

The foreign secretary told Sarah Pochin to “get some help” after she suggested the government’s controversial decision to give the Chagos Islands to Mauritius had played a part in America’s plans for bombing Iran.

The pair clashed after Lammy updated parliament about the worsening crisis in the Middle East.

It was thought that the UK may have to give the US permission to use the Diego Garcia air base in the Chagos Islands to launch its attacks on Iranian nuclear weapons facilities.

But in the end, the American aircraft flew non-stop from the US on their bombing mission.

Pochin, the MP for Runcorn and Helsby, said: “Can the foreign secretary explain to the House whether the United States felt unable to use the Diego Garcia base … because of your deal that you did with the Mauritians, that would then tell the Chinese, that would then tell the Iranians?”

Lammy told her: “The honourable lady has got to get off social media, has got to get some help because she’s swallowing conspiracy theories which should not be repeated in this House.”