For most prime ministers, the certain knowledge that their premiership is coming to an end sparks a frenetic final effort to complete as much of their policy agendas as possible and secure a legacy. Yet Boris Johnson’s decision to spend his last months thanking supporters at Chequers, holding a wedding party and taking a holiday weeks before his time in Downing St expires is an “enigmatic end for an enigmatic premiership”, according to one of the country’s best-known contemporary historians. Sir Anthony Seldon, who has written books on the Blair, Brown, Cameron and May premierships and studied the impossible job prime ministers face, said Johnson’s approach contrasted sharply with that of his predecessors who had the luxury of planning their final weeks. He said that Tony Blair and Theresa May – two recent prime ministers who knew their time in office was ending – both scrambled hard to ensure their final weeks were not wasted. David Cameron also planned some final measures, only to have his premiership end prematurely after Andrea Leadsom pulled out of the Tory leadership race and May was crowned prime minister. In contrast, Seldon said, Johnson’s final weeks have been “lackadaisical” since he announced he was resigning. “What happens is that prime ministers are either blown away by a general election, like John Major or Gordon Brown, or by a collapsing leadership election, as was the case with Cameron,” Seldon said. “He wanted to do all sorts of things with his last six weeks. “But when they do have the time, like Theresa May, they use it to really do all the things that they would have done early on, had they had a better sense of the rhythm of the architecture of a premiership. Blair also planned his departure very carefully and did keep going to the very end. He choreographed his departure and how to maximise those final weeks. “Whereas this is all lackadaisical. It’s odd because the story of the Johnson premiership is of incomplete work. The things he cared about – levelling up, getting the Brexit dividend, creating the strong economy, creating a strong position for Britain in the world, being the most decisive prime minister on the environment – these things are not complete. “A lot of the others had a whole series of speeches they delivered to finish things as they would want to finish them. Maybe that’s going to come, but the timing is acute for him because the country is going to be on holiday until the beginning of September, and then the interest isn’t going to be on him.” Johnson was accused of going “missing in action” last week, after it emerged he went on holiday to an undisclosed location just weeks before his premiership ends. Last month, he held a drinks gathering at his Chequers country retreat during the heatwave, while cabinet office minister Kit Malthouse oversaw Cobra meetings on the extreme weather. He held his wedding party the following weekend at the Cotswolds estate of major Tory donor Lord Bamford. It is said to have included a steel band, rum punch, Abba songs and a conga. He had previously been photographed flying in a typhoon and training with Ukrainian troops. Johnson went on holiday on Wednesday. Seldon said that, unlike his predecessors who found themselves in a similar situation, Johnson has made No 10 a “hive of inactivity”. “That would be rational behaviour for somebody who had done the jobs that he wanted to do,” he said. “He hasn’t done those things. It would be rational behaviour for somebody extremely diligent who had come in with all guns blazing. He didn’t do that. “He’s finishing true to himself. Everything about him is counter to expectation.” A No 10 spokesperson said: “The prime minister has always been clear this government should be judged on its actions delivering for the British people – from taking back control and leaving the EU, protecting lives and livelihood during the pandemic and rolling out our world-leading vaccination programme, to leading the global response to the conflict in Ukraine. “While he has set out his intention to step down when a new leader is in place, the Prime Minister remains focused on driving forward his commitments to the public. Not least ensuring families are accessing the £37bn worth of support for households facing rising costs as a result of Putin’s illegal war.”