Labour MPs were on Monday night being canvassed by potential leadership rivals to Andy Burnham, after the hot favourite to take over as British prime minister from Keir Starmer was sworn in to the House of Commons following his Makerfield byelection win.Up to 200 Labour MPs – half of the parliamentary party – turned up in Westminster Hall to greet Burnham, hours after Starmer announced his intention resign in an emotional speech on Downing Street. Burnham confirmed he would seek to replace Starmer as Labour leader and UK prime minister.Burnham’s potential path to Number 10 had been smoothed when his biggest rival for the leadership, former health secretary Wes Streeting, earlier said he would not run and threw his support behind the former Greater Manchester mayor.Streeting denied that he had been offered a job by Burnham to stand aside, amid rumours that he did not have enough support to challenge him. Keir Starmer hugs his wife Victoria after announcing his resignation as UK prime minister. Photograph: Peter Nicholls/Getty Images One MP on Monday said Streeting’s decision to make way was borne not of a deal, but a “surrender”.However, a handful of other outside-bet candidates had still not ruled themselves out of the race and appeared to be jockeying for position last night. Supporters of Darren Jones, chief secretary to the prime minister, were said to be ringing around their Labour parliamentary colleagues to gauge if he had enough support for a leadership bid.Al Carns, who quit this month as armed forces minister in a row over military funding, also appeared to set out his stall on Monday with an article in party-linked publication Labour List laying out his ideas on a range of matters.Foreign journalists were also invited to a hastily-arranged press conference on Tuesday morning with Carns. The event, called at just 18 hours notice, is being hosted by the Foreign Press Association, which billed it as a meeting with a “potential Burnham rival”.Carns and Jones may struggle, however, to attract the 81 Labour MPs whose backing they would need to enter the race to replace Starmer. Burnham’s overwhelming support in the parliamentary party means there might not be enough MPs for other contenders.Nominations for the leadership open on July 9th and close when parliament enters recess on July 17th. If Burnham is unopposed, he would then become prime minister.If Carns, Jones or another contender can cobble together enough support, a contest would be held over the rest of the summer to win the backing of Labour members, before a new prime minister would take over at the start of September.Starmer said he would stay on until his successor was chosen.In his resignation speech at 9.30am at Downing Street, the UK prime minister became emotional as he paid tribute to his family.He said six years ago he had inherited a Labour Party that was “politically, financially and morally bankrupt”, but he had turned its fortunes around. Polls show he is deeply unpopular with voters, however and Starmer said he accepted the decision of his MPs that he should no longer lead them.His last international outing is likely to be a July 7th and 8th meeting in Turkey of the Nato military alliance. A planned summit between the UK and European Union for July 22nd was postponed.Taoiseach Micheál Martin commended Starmer for “resetting the Irish-British relationship as well as relations between the UK and the EU”.