Theresa May was accused of misleading parliament by claiming the SNP did not have a plan for independence.
Ian Blackford, the Nationalist leader in Westminster, brandished the party’s 2014 white paper on leaving the UK when he challenged Mrs May after Prime Minister’s Questions.
Asked earlier by the Highland MP about delaying Brexit to avoid economic disaster, she said: “He complains about no deal, but of course, it was the Scottish National Party who wanted to leave the UK without a plan.”
In a point of order, Mr Blackford held aloft the controversial masterplan for an independent Scotland as he suggested the Conservative leader “perhaps inadvertently misled the House when she said that there was no plan for Scottish independence”.
Douglas Ross, the Scottish Conservative MP, weighed in saying the paper contained “many errors and omissions”, including that it “wildly overstated the predicted revenue from oil”.
Mr Blackford withdrew his “liar” slur against the PM on Tuesday in testy exchanges during a Brexit statement.
Last year, the Ross, Skye and Lochaber MP promised “maximum disruption” in the Commons if the UK Government continued to ignore Scotland’s interests.