A SENIOR SNP MP has criticised Andrew Wilson after he urged a gradual build-up to the “softest possible” form of independence.

Joanna Cherry QC, the SNP’s justice spokeswoman at Westminster, took to Twitter to disagree with Wilson, the author of the party’s Growth Commission and a weekly columnist in The National.

She said independence was needed as soon as possible to protect Scotland from Brexit, and promoted the call for a second referendum.

Wilson, a former MSP , said on Thursday that Nicola Sturgeon should play a long game on independence in order to woo voters and “win big”.

He wrote in The National: “In the parlance of Brexit, we offer the softest of possible changes to the current arrangements, not the hardest. We recognise the level of integration and all the ties that have bound us for centuries. We create a platform that can unify a majority for progress that stands a chance of winning and winning big.”

He said more time was needed to recast the 2014 case for independence, likened leaving the UK to a “process rather than an event” and said Scotland was on a “journey without end”.

He also criticised Yes supporters who want independence to be swifter and more radical.

“Some (a very small number) would rather move immediately and overnight to a Marxist revolutionary state. That is their right, but they won’t win the chance to try,” he said.

The comments drew a sharp response from Cherry on Twitter.

She said: “You don’t have to be a ‘Marxist revolutionary’ to disagree with this softly softly strategy. Brexit is a catastrophe about to hit Scotland & the only way to protect our society & economy is #independence #indyref2.”

In a second tweet, she added: “As an MP on the #Brexit Select committee I’ve watched this disaster proceed in the face of all the evidence. I’m also aware that many of #EU27 are very sympathetic to #independence for Scotland & once UK is 3rd state that can translate to action #indyref2.”

Cherry’s intervention is the latest development among SNP figures in a debate over the timing of a new independence referendum and come as the First Minister is expected to announce her plans regarding a possible new vote in weeks.

Supporters of an early referendum include the MP Angus Brendan MacNeil, who has called for a fresh vote this year, and the former MP George Kerevan who also supports a vote in the short term. But others back a longer term approach. They include the Glasgow South MP Stewart McDonald, who recently said his party would be rejected by voters if it tried to “bounce” the country into a second independence referendum. McDonald, who is the party’s defence spokesman, also said it would be the “height of irresponsibility” to try and rehash the Yes campaign of 2014, and its tenor needed to “utterly change”.

Alyn Smith, the MEP, also backs a longer term strategy, saying last month: “I don’t think we’re ready to press the button on a independence referendum yet, because there are too many moving parts to Brexit.”