Labour supporters of Wes Streeting and Andy Burnham have been accused by deputy prime minister David Lammy of “lighting a match and standing in the petrol” of the party’s destruction.The provocative remarks by Mr Lammy, a close ally of Sir Keir Starmer, came as he said the prime minister would fight to survive if a Labour leadership contest is triggered.Mr Lammy said if such a battle took place over the next ten weeks the party would be out of office and it would pave the way for Nigel Farage to take power.He dismissed Mr Streeting’s call for the UK to rejoin the EU as a “sixth form debate”, saying Labour’s task was to deliver on its election pledges.Mr Lammy claimed Sir Keir would survive Mr Streeting’s resignation, just as Margaret Thatcher and Tony Blair had survived the resignations of Cabinet critics Michael Heseltine and Robin Cook respectively after similar disagreements.Sir Keir Starmer is not planning to set out a timetable for departure, David Lammy has said (Getty)Commenting on the Labour infighting over moves to replace Starmer, Mr Lammy said: “Introspection, internecine warfare? Effectively, some of our colleagues are lighting the match and standing in the petrol.“That is not going to deliver on behalf of the British people. That will usher in Farage.”He described the Labour turmoil in the ten days following Mr Streeting’s resignation as health secretary as “an extraordinary own goal”.Asked about Mr Streeting’s comments about reversing Brexit he said: “Wes Streeting is free to say what he wants. I am not going to speculate about the next Labour manifesto.“This is not a sixth form debate, it is about delivery on behalf of the British people.”Former health secretary Wes Streeting REUTERS/Jaimi Joy (Reuters)Unless uncertainty over the prime minister’s position was brought to an end Labour would be “desperate trouble, we will be out of office and what we will be ushering in is Farage,” said Mr Lammy.He told the BBC he was “very sad when Wes Streeting decided to leave the government”.However, he added: “But just as Michael Heseltine left Thatcher’s government, just as Robin Cook left Blair’s government, just as James Purnell left Brown’s government, people do resign when they cannot sign up to collective (cabinet) responsibility.”Sir Keir was “the most resilient person I know” and Mr Lammy appealed to Labour MPs was to show more “discipline” and be “loyal” to him.