Scottish Secretary David Mundell has been urged to resign if he does not oppose a no-deal Brexit.
SNP Westminster leader Ian Blackford wrote to Mr Mundell calling on him to back an extension of Article 50 in order to avoid the UK leaving the EU without a deal in place.
The UK is due to depart on March 29, however there is no agreement at Westminster over a deal after Prime Minister Theresa May’s proposals were rejected.
Mr Blackford suggested in his letter to the Scottish Secretary that he should publicly threaten to quit the Cabinet if the UK Government is prepared to allow a no-deal Brexit.
The SNP MP also referred in his letter to a report published on Thursday by Scotland’s top economic adviser which suggested that a no-deal scenario could result in a recession worse than 2008.
Mr Blackford said: “Crashing out of the EU with either Theresa May’s bad deal, or with no deal at all, is a false choice that would be disastrous for Scotland – destroying jobs, damaging living standards, and leaving the whole country poorer and worse off.
“Time is running out and the only way to prevent a bad deal for Scotland is to extend Article 50, and put the brakes on Brexit, to find a credible solution that protects jobs and the economy.
“Scotland did not vote for Brexit, and we must not be dragged out of the EU against our will. It is time that the Scottish Secretary actually did his job for once by standing up for Scotland’s interests.
“David Mundell must finally back SNP calls to extend Article 50, and make it clear that he will not serve in a UK government that is willing to impose a no-deal Brexit on Scotland.
“Westminster is failing Scotland. If the UK parliament continues to ignore our wishes and work against our interests, then it is clearer than ever that our interests can only be protected with independence.”
The Scottish Secretary has previously suggested to MPs that the best way to avoid no-deal Brexit would be to vote for the Prime Minister’s deal.
A UK Government source said: “This is gross hypocrisy from the SNP. The SNP are doing their best to bring about a no deal, despite knowing the damage that would do to Scotland. They are only interested in their own divisive, nationalist agenda, not what is best for Scotland.”