(Bloomberg) -- Boris Johnson is used to critical newspaper front pages, but mainly from Conservative-skeptic titles. Thursday morning was different.

“Beginning of the end for Boris?” was a front-page headline in the Daily Telegraph, the Tory-supporting paper for which Johnson worked as Brussels correspondent and later political columnist.

“One rule for them, new rules for the rest of us,” blared the Conservative-leaning Daily Mail, widely viewed as the voice of middle-class voters.

Though Johnson’s botched handling of an ethics probe last month triggered some critical headlines, it was his announcement Wednesday of tighter Covid curbs that has really pushed them over the edge. The introduction of work from home guidance and mandatory vaccine passports came amid a public outcry over allegations of Downing Street parties when they were banned last year.

It was the Labour-supporting Daily Mirror that broke the story of last year’s Downing Street party, and it’s taken a while for the Conservative-backing newspapers to catch up with the outrage.

But a video that emerged of key aides joking about the festivities sparked anger on all sides -- and that could be dangerous for Johnson. The Sun described him as a “Grinch PM” -- in reference to Dr Seuss’ grumpy character -- along with the headline: “Do as I say, not as I Christmas do.”

The response of the right-leaning newspapers echoes growing concerns among Johnson’s own ruling Conservative party over his leadership, following a series of self-inflicted crises in the last few months. The Tories slumped in the polls, while Johnson’s own approval rating is at the lowest of his premiership.

Conservative MPs are becoming more openly critical toward Johnson, who led the party to an emphatic victory in 2019 and won a slew of seats in northern England that had long been considered Labour heartlands.

The Daily Mail, which long supported Johnson, has also taken a tougher line in recent days. “A sick joke” headlined their front page report on the Christmas party video.

That’s despite the recent departure of Geordie Greig -- an anti-Brexit, liberal figure -- as editor, and the appointment of Ted Verity, who many thought would be less likely to run critical coverage of Johnson’s Conservatives.

The question for Johnson, who pores over the newspapers as a former journalist himself, is how long the critical front pages keep running. He will be hoping the Parliament break over Christmas allows the furor to calm. 

But with a House of Commons vote on the new Covid restrictions on Tuesday, he can expect more negative headlines from the Tory press for a while yet.

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