IT will be very difficult for Boris Johnson to recover from the partygate scandal, leading polling expert John Curtice has indicated as he said the PM is "fighting a losing battle" in trying to convince voters he didn't break Covid rules.

Johnson has continued to come under pressure from political opponents to resign amid the scandal that has taken over UK politics in recent months.

However, he is not likely to step down voluntarily and may face a vote of no confidence in his leadership of the Conservative Party.

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Polling expert Professor John Curtice of Strathclyde University told The Independent that while Johnson attempts to win back support of Tory MPs, public opinion against him has hardened which is "very difficult to reverse".

Curtice said that his own analysis of recent polls show that 41% of people who voted for the Tories in 2019 think Johnson should resign.

A recent poll by Opinium showed that three-quarters (75%) of 2019 Tory voters think Johnson broke his own Covid rules with parties and other events held in Downing Street during the strict lockdowns.

Some 61% of Tory voters also believe that Johnson is not telling the truth in his explanations about parties and Curtice says this is a "real problem" for the PM, saying that the question now is: "What will they believe him on in future?”

The National: Polling expert Professor John Curtice of Strathclyde UniversityPolling expert Professor John Curtice of Strathclyde University

He added: “Political parties can recover from electoral trouble. But leaders rarely recover, once a leader becomes very unpopular. It’s very difficult to reverse.

“So far, Boris Johnson is fighting a losing battle in persuading people that he did not break the rules … The art of rhetoric, at which he is brilliant, may not be sufficient to enable him to restore his reputation.”

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Johnson's initial explanation describing a lockdown-busting party as "work event" at the May 2020 garden gathering damaged the Prime Minister's appeal to voters, according to Curtice who compared it to former No 10 adviser Dominic Cummings trip to Barnard Castle.

The National: Dominic Cummings took a trip to Barnard Castle to 'check his eyesight'Dominic Cummings took a trip to Barnard Castle to 'check his eyesight'

Curtice said: "We know from the Barnard Castle episode that people regard rule-breakers during a public health crisis with a great deal of moral disapprobation. The phrase ‘work event’ has entered the lexicon in the same way Barnard Castle did."

Cummings's trip to Barnard Castle summoned furore in Johnson's former top aide after he explained he took a trip to the Durham town to test his eyesight after having Covid.

The man who masterminded the Vote Leave Brexit campaign took a trip to visit his family in Durham while there were strict rules not to travel outside your local area.