PMQs: Johnson and Blackford on election candidates Gray and Ross
The prime minister has been asked to make his Scottish leader stand down from his Westminster seat as he bids to become an MSP.
The SNP's Ian Blackford said one of his MPs has resigned ahead of standing for Holyrood in May, but that Tory Douglas Ross has not stood down in similar circumstances.
Boris Johnson said the SNP had a "one-track record" over an independence referendum and asked if the party was "getting nervous of singing that particular song", although he called Mr Ross by the name "Moray Ross", confusing his name with his constituency.