Ian Blackford has branded Boris Johnson the “last Prime Minister of the UK” in Mr Johnson’s first Prime Minister’s Questions as leader.
The SNP MP said: “Scotland will not stand by and let decisions be taken by charlatans on our behalf.”
“He [Boris Johnson] wants to drive us off the cliff edge and he does not even know of the impact of the damage it will cause. This is the height of irresponsibility.”
He added: “Scotland's First Minister has been clear - that she's now reviewing the timetable for a second independence referendum.”
In her first letter to Mr Johnson, Scotland’s First Minister Nicola Sturgeon has renewed her demands for a fresh vote on Scottish independence.
She said it was “more than ever essential that in Scotland we have an alternative option” to Brexit.
Ms Sturgeon recently suggested a second vote to leave the UK in an effort to remain in the European Union could take place as early as next year.
Mr Johnson is opposed to a second vote and told Mr Blackford a successful Brexit would silence the SNP.
“Will they seriously continue to say Scotland must join the Euro? Will they seriously suggest that Scotland must submit to the entire panoply of EU law?” he said.
“We will win on a manifesto for the whole United Kingdom.”
Mr Blackford said Parliament must respect the “right of the people in Scotland to determine their own future”.