Boris Johnson was greeted with applause and cheers when he joined one of the final events of the Conservative Party’s General Election campaign.

The former prime minister has been largely absent from the campaign, although supportive in his newspaper column, and has been writing letters of endorsement and backing a number of Tories in social media posts.

As he stepped onto the stage at the National Army Museum on Tuesday, less than 48 hours before polls open, Mr Johnson was greeted by applause and chants of “Boris, Boris, Boris”.

He thanked attendees at the late evening event for “coming so late, way past Keir Starmer’s bedtime” in a dig at the Labour leader’s comment that he largely avoids working after 6pm on Fridays to spend time with his family.

Mr Johnson added: “When Rishi asked me to come and help of course I couldn’t say no.

“We’re all here because we love our country.”

Mr Johnson told the audience a Labour government would increase taxes and would not stand up to Vladimir Putin.

“They will scrap the Rwanda plan,” he said before describing Labour MPs as “Kremlin crawlers”.

Mr Johnson, who led the Tories to a landslide victory in 2019 against a Labour Party led by Jeremy Corbyn, told cheering crowds: “They can achieve nothing in this election except to usher in the most left-wing Labour government since the war with a huge majority, and we must not let it happen.

“Don’t let the Putinistas deliver the Corbynistas. Don’t let Putin’s pet parrots give this entire country psittacosis – which is a disease you get by the way from cosying up to pet parrots.

“Friends, if you actually – everybody if you actually want higher taxes next week, this year, if you feel you’ve got a few thousands to spare, then vote Labour on Thursday. If you want uncontrolled immigration and mandatory wokery, and pointless kowtowing to Brussels again, then go right ahead, make my day, vote for Starmer.

“But if you want to protect our democracy and our economy and keep this country strong abroad by spending 2.5% of our GDP on defence which Labour still refuses to commit to, then you know what to do, don’t you, everybody?

“There’s only one thing to do – vote Conservative on Thursday my friends and I know you will. I know you will.”

Liberal Democrat deputy leader Daisy Cooper described Mr Johnson’s appearance as “a desperate new low” for Mr Sunak’s campaign.

“This is an insult to everyone who made heart-breaking sacrifices during the pandemic,” she said.

“Rishi Sunak has reached a desperate new low, turning to a man who discredited the office of prime minister and lied to the country time after time.