Boris Johnson has been dealt a devastating blow after his chief Scottish Law officer, Lord Keen, offered to quit over the government's plan to breach international law.
The Advocate General for Scotland tendered his resignation after 24 hours of confusion over the Internal Market Bill.
Keen said: "I tendered my resignation to the Prime Minister first thing this morning, I've not heard back from the Prime Minister."
He had told the House of Lords on Tuesday the government's post-Brexit internal trade plan does not "constitute a breach of international law or of the rule of law". He said Northern Irish Secretary Brandon Lewis had "answered the wrong question" in the Commons when he said the bill would break the EU Withdrawal Agreement in a "specific and limited" way.
But Keen, the Advocate General for Scotland, was then humiliated on Wednesday morning when Lewis insisted he was right and the law officer was wrong.
A frantic Downing Street operation has been launched to persuade the Advocate General to stay in post. Officials fear no other member of the Faculty of Advocates, the Scottish Bar, can be persuaded to take up the essential post in the UK government.
The SNP's Joanna Cherry MP, a QC and party spokeswoman on legal matters, tweeted: "One UK Govt Law Officer down. Two to go. I know the English bar shares the commitment to the rule of law of the Scottish Bar so how long can the Solicitor General Mike Ellis and Attorney General Suella Braverman remain in post?"
The fiasco was highlighted at Prime Minister's Questions when Orkney and Shetland MP Alistair Carmichael asked about the confused logic of the government.
He said: “Last week the Secretary of State for Northern Ireland said that the UK Internal Market Bill would breach our obligations under international law. Yesterday the Advocate General for Scotland said that the Secretary of Sate was wrong to say that.
“Today the Secretary of State says that the Advocate General was wrong to say that he was wrong. Now it's of course possible that they are both right in saying that the other is wrong, but surely an important matter such as this requires clarity.
“For that reason will the Prime Minister now undertake to publish the advice he’s had from all his law officers so that the House can make an informed decision on the question of legality come Monday?”
Johnson replied that the government does not publish legal advice it receives, leaving the question of who said what wrong or right still hanging in the air.
The PM is due in front of MPs on the Commons Liaison Committee at 3.30pm on Wednesday.
