IAN Blackford has challenged Boris Johnson to “come out of hiding” to answer questions about an alleged Downing Street cover-up over Dominic Cummings’s lockdown breach.

The SNP Westminster leader spoke out after reports surfaced that the PM’s top adviser made a second trip to County Durham despite social distancing restrictions.

Johnson has pledged his "full support" to the former Vote Leave chief, who it emerged had travelled 260 miles to the north east of England in March to self-isolate with his family while official guidelines warned against long-distance journeys.

According to the Sunday Times, the Conservative Party leader told allies he would not throw Cummings "to the dogs”.

So far, the only Tory minister to face questions from the media has been Transport Secretary Grant Shapps, who insisted Cummings did not make a second visit to Durham.

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But Blackford called on the Prime Minister to front up to scrutiny.

He said: "Boris Johnson now has very serious questions to answer about his judgement and integrity.

"The Prime Minister cannot dodge scrutiny any longer. He must come out of hiding, turn up to today's press conference, and put on the record what he knew about Dominic Cummings' rule-breaking and whether he played a role in the Downing Street cover-up.

"It is beyond doubt that Dominic Cummings broke multiple lockdown rules, possibly on multiple occasions. As Scottish Tory leader Jackson Carlaw said: 'There cannot be one rule for bosses and another for everyone else'. Mr Cummings must go – or Boris Johnson must sack him.”

Blackford said he was not surprised several Tory MPs have now broken ranks to demand that the Prime Minister dismissed his top adviser. A snap YouGov poll also showed the majority of people in the UK thought Cummings should quit.

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The SNP Westminster leader continued: "The excuses are not credible and do not stack up. It's no wonder there is now a mounting rebellion of Tory MPs who are demanding Mr Cummings go. They understand the lasting damage this is doing to public confidence in the Tory government and its covid-19 response.

"The SNP will continue to press for a Cabinet Office inquiry into the breaking of the rules and the Downing Street cover-up, which left the public in the dark for so long.

"Polling shows the majority of the public want Mr Cummings to go. With every hour the Prime Minister allows this farce to continue – the Tory government loses more credibility and respect."

Responding to reports, first published in the Observer and Sunday Mirror that the PM’s adviser made a second trip to Durham, Downing Street said it would "not waste time" replying to allegations from "campaigning newspapers".