A memoir by former prime minister Boris Johnson, covering his years as leader, will be published by HarperCollins, it has been announced.

The book, which so far has no title or publication date, will be a “prime ministerial memoir like no other”, according to Arabella Pike, publishing director at William Collins, an imprint of HarperCollins UK.

“I look forward to working with Boris Johnson as he writes his account of his time in office during some of the most momentous events the United Kingdom has seen in recent times,” she said.

It is not known how much Johnson was paid for the book, but industry insiders told the Guardian last year that he could receive “a high six-figure or even a seven-figure deal”.

Johnson’s time as prime minister was characterised by a string of scandals, from the amount of public money he spent on decorating his Downing Street flat to Partygate.

Johnson worked as a journalist before becoming prime minister, and there had been speculation that he would return to writing after taking a step back from politics.

He worked as editor of the Spectator from 1999 to 2005 and as a columnist for the Telegraph. His previously published books include The Churchill Factor, a bestseller published in 2014 that looked at the career and success of Winston Churchill.

Recent prime ministers who have written memoirs include David Cameron, whose For the Record was sold in a “hotly contested and significant” deal, while Gordon Brown’s My Life, Our Times was sold for an “undisclosed sum”. Tony Blair’s A Journey was reportedly sold for an advance of about £4.6m, although all the money he made was donated to the Royal British Legion.

HarperCollins US will publish Johnson’s book at the same time as it is published in the UK.