Keir Starmer sought to repair fraught relations with Donald Trump over the war in Iran on Sunday, as a Labour backlash gathered pace over Tony Blair’s assertion that the UK should have supported the US’s initial airstrikes on Iran.

The prime minister spoke to the US president on Sunday afternoon following a barrage of criticism from Trump, who told his UK ally on Saturday that his help was not needed, even as the US continued to use UK bases for Iran strikes.

After a breakdown in relations between Trump and Starmer that led Trump to declare on social media that “We don’t need people that join Wars after we’ve already won!”, the two world leaders spoke on Sunday to discuss their nations’ military cooperation.

A Downing Street spokesperson said the leaders “began by discussing the latest situation in the Middle East and the military cooperation between the UK and US through the use of RAF bases in support of the collective self-defence of partners in the region”.

They added that Starmer also “shared his heartfelt condolences with President Trump and the American people following the deaths of six US soldiers” and the two leaders “looked forward to speaking again soon”.

The call comes after Blair riled Labour senior figures and backbenchers after telling a private gathering that Starmer “should have backed America from the very beginning” and let the Trump administration use British airbases. He added: “If they are your ally and they are an indispensable cornerstone for your security … you had better show up when they want you to.”

Yvette Cooper rejected the former prime minister’s comments, saying she “disagreed” and added that Britain had to “learn the lessons” of mistakes made in Iraq. “I don’t think either of those positions is in the UK national interest, and it is the responsibility for Keir Starmer to act in the UK’s national interest for British citizens,” she told Sunday Morning with Trevor Phillips on Sky News.

Asked if she was calling Blair “a poodle”, she said: “I think the point is to make sure that, actually, we learn the lessons from some of the things that went wrong in Iraq, and I think that is exactly what Keir Starmer has done.”

The call between Trump and Starmer came as four US bombers landed at an RAF base in Britain on Sunday afternoon to carry out “specific defensive operations” to stop Iran firing missiles into the Middle East, according to the Ministry of Defence.

The B-1 Lancers, which are 45 metres (146ft) long and capable of carrying 24 cruise missiles, arrived at RAF Fairford in Gloucestershire, one on Friday evening and three on Saturday morning, after Starmer previously granted permission for “defensive” US action against Iranian missile sites from UK bases.

The deployment comes days after Washington warned that strikes on Iran would “surge dramatically”.