Dominic Grieve says Boris Johnson would have to quit if it is found he lied to the Queen (Picture: Getty)

Boris Johnson should resign if he is found to have misled the Queen, a former Tory Attorney General has said.

Dominic Grieve said the Prime Minister’s position would be ‘untenable’ if it is found that he misled the monarch over the reasons for proroguing Parliament.

Mr Grieve, who was sacked by Mr Johnson last week after voting to block a no-deal Brexit, spoke after three judges in Edinburgh found the suspension of Parliament was unlawful.

The UK government has said it will appeal against the ruling and it is expected there will be a ‘major showdown’ at the Supreme Court.




Mr Grieve told BBC News: ‘It is absolutely central to our constitution that the relationship between the Prime Minister and the Queen is one of the utmost confidentiality and the utmost good faith.

‘If it were to be the case that the Government had misled the Queen about the reasons for suspending Parliament and the motives for it – that would be a very serious matter indeed.

‘Indeed in my view, it would then be the moment for Mr Johnson to resign – and very swiftly.’

Boris Johnson got the green light to suspend Parliament from the Queen after he sent a team, including Jacob Rees-Mogg, to Balmoral on his behalf (Picture: PA)

He added: ‘I think that if that were to be the case that this had happened, Boris Johnson would find himself in an untenable position in Parliament.

‘And I hope it would be untenable not just because of the opposition, but because actually every member of the Conservative Party that believes in our constitution would simply say it’s over.’

Mr Johnson is facing furious demands for the immediate recall of MPs to Westminster after the suspension of Parliament was ruled unlawful by Scotland’s highest civil court.

In a dramatic judgement, the Court of Session, found ministers had stopped MPs from sitting for the ‘improper purpose of stymying Parliament.’

It said advice given by ministers to the Queen which led to the five-week prorogation was therefore ‘unlawful and is thus null and of no effect.’

Boris Johnson’s government immediately announced it was lodging an appeal and a hearing is set at the Supreme Court for Tuesday.

Opposition MPs say in the meantime they should return to Westminster as the clock ticks on the current Brexit deadline of October 31.

Dominic Grieve was sacked by Boris Johnson after he joined with the opposition to force no-deal off the table (Picture: AFP)

Downing Street maintains that the five-week suspension is so that the new Government could set out its legislative programme ahead of the Queen’s speech on October 14.

The suspension effectively halved the number of pre-Brexit days that MPs were sitting but Mr Johnson denied that he wanted to thwart discussion on the subject.

Officials have said that Parliament will remain prorogued despite the fact many potential laws have now stalled.