The SNP's Westminster leader had to approach RBS bosses directly in a bid to halt the closures of 62 banks in Scotland.

He told the BBC that he "bypassed" the Prime Minister to discuss directly the potential impact of losing such "vital" local services in communities.

Some of the proposed closures are in remote and rural areas where there is only one bank.

The MP for Ross, Skye and Lochaber accused the Tories of "failing to lift a finger" to save them.

Ian Blackford also revealed that he is "very close" to reaching a deal with the bank that could grant a reprieve for some of the the closure-threatened branches.

He said: "I've had a number of conversations and meetings with the Royal Bank of Scotland over the last few weeks.

"Really what I've tried to put across and what other colleagues have tried to put across is the very real threat to a number of communities, in particular where they have been talking about closing the last bank in town.

"And I've been encouraged by the the positive nature of the talks we've been having. These talks are ongoing, but I hope that we are very close to a resolution that can give some hope to a number of communities that Royal Bank of Scotland branches can remain open."

The Royal Bank of Scotland claims the plans are in response to changes in customer behaviour including a rise in digital banking.

But Mr Blackford has been accused by Conservative MP Colin Clark of "undermining" the all-party Scottish Affairs Committee at Westminster, chaired by the SNP's Pete Wishart, by trying "to get the headline" on the issue.

The Labour shadow Scottish secretary Lesley Laird warned of "back room deals" between the SNP and RBS.

She said: "I am astounded that Ian Blackford is cutting across a live investigation being undertaken by the Scottish Select Committee into RBS and its proposals to close vital high-street bank branches.

"There should be no back room deals done with RBS and I hope that is not precisely what Peter Wishart, who is chair of the committee, and Ian Blackford are doing."

Ms Laird added: "While we are frustrated at the Tory Government's lack of action, it is still not right that two SNP MPs get to decide which branches in which communities get to stay open."