Angus Robertson has claimed Scotland is “on the brink of independence” as he launched his bid for the deputy leadership of the SNP.
The Moray MP, who is in the running to be Nicola Sturgeon’s number two, said he had a “big role” to offer in a campaign which was “all about persuading people why our vision is the right one”.
Mr Robertson’s comments came as new figures showed the SNP’s membership had passed 120,000 in the aftermath of the Brexit vote.
The role of the SNP deputy leader has been vacant since Dundee MP Stewart Hosie stood down, citing concerns about his health after allegations emerged about his private life.
Westminster group leader Mr Robertson said: “We know that we are on the brink of independence. The campaign that comes now should be all about persuading people why our vision is the right one for Scotland.
“The SNP depute leader has a big role in order to make this happen – developing our policy, strategy and tactics to win.”
Mr Robertson insisted he had the “ability to build on the strong relationship that already exists” between his group, MSPs in Holyrood and party members.
The former journalist is aiming to recruit 5000 pledged supporters before nominations close on August 5.
Fellow Westminster MP Tommy Sheppard, Alyn Smith MEP and Inverclyde Councillor Christopher McEleny have also thrown their hats into the ring.
The new deputy leader will be announced at the party’s autumn conference later this year.
Earlier, SNP business convener Derek Mackay welcomed the surge in membership for the SNP since last month’s EU referendum.
More than 4,000 new members joined the party after Scotland voted to remain in the EU, but a majority across the UK voted to leave.
Mr Mackay said: “The incredible upsurge in SNP membership shows no signs of stopping. With membership now over 120,000, this puts the party in a strong position as we deliver our ambitious manifesto in government and lead the opposition to the Tories at Westminster.
“That membership has grown substantially since the EU referendum vote is testament to the strength of feeling in Scotland that we must not be dragged out Europe against our will.
“And the SNP in government will continue to explore every option to maintain our EU status.”