Nicola Sturgeon risks becoming a “laughing stock” over her claim that her election campaign has nothing to do with independence, Ruth Davidson has said as grassroots nationalists urged the SNP to make the link “explicit and undeniable”.

The Scottish Tory leader poured scorn on the First Minister’s attempt to decouple her recent demand for a second referendum from the general election, asking “who does she think she is kidding?”

She said Ms Sturgeon may have told her members not to mention “the ‘i’ word” on the doorsteps but the SNP has always used gains in previous elections to push the case for separation.

David Mundell, the Scottish Secretary, said the SNP leader’s attempts to distance her general election campaign from her independence push and her personal attacks on Ms Davidson showed she was “rattled” by polls showing the Tories winning up to 12 seats in Scotland, including 10 from her party.