Boris Johnson has earned nearly £5mn since leaving office

Boris Johnson has declared income of £4.8mn since he left office last September, more than 50 times his salary of £84,144 as a backbench MP.

The former prime minister on Wednesday declared an advance payment of £2,488,387.53 from New York’s Harry Walker Agency for giving an unspecified number of future speaking engagements.

The speaking agency represents some of the biggest names in American politics, including former presidents Bill Clinton and Barack Obama.

Johnson was forced out of Downing Street in July by mutinous Tory MPs over a series of scandals including “partygate”, which saw scores of Whitehall staff — and Johnson himself — fined for taking part in illicit gatherings during Covid-19 lockdowns.

Since then he has remained on the backbenches as MP for the constituency of Uxbridge and South Ruislip, but according to the MPs’ register of financial interests his income has jumped in just months from a book advance and speeches that earn him close to a quarter of a million pounds at a time.

In January alone his earnings from speeches included £246,406 from Bloomberg Singapore and £200,892 from Aditya Birla Management, an Indian company, according to the register.

The lucrative engagements come despite him telling MPs in 2021 that they should focus on their parliamentary duties. “You must put your job as an MP first and you must devote yourself primarily and above all to your constituents,” he said.

Johnson has declared a £510,000 advance with HarperCollins to publish a memoir chronicling his turbulent three-year period as prime minister during Brexit and the pandemic. He has already written a dozen books, but has yet to complete a biography of William Shakespeare, first promised eight years ago.

Last month Johnson declared that he had received £1mn from Christopher Harborne, a tycoon who previously funded the Brexit party. The money has gone towards an organisation called The Office of Boris Johnson Ltd, which was set up to support the former prime minister’s public life by funding an office with three staff.

Meanwhile, the former prime minister has for the past five months lived in a £20mn property on one of Britain’s most expensive streets in Knightsbridge, central London. The house is owned by Lady Carole Bamford, wife of the JCB construction equipment tycoon and Tory peer Lord Anthony Bamford.

In the register Johnson has declared the “concessionary use of accommodation for me and…