The slump also follows controversy over vaccine passports. Two months ago, the PM had a net approval rating of 55.6.

In contrast, Mr Sunak‘s reputation appears to be almost unaffected. He remains the second most popular member of the Cabinet with Tory activists, with a net approval rating of 74.1.

The most recent survey also found that a narrow majority of Tory activists now believe the PM is dealing with the pandemic ‘badly’.