ALEX Salmond claims Theresa May's "lack of stature is becoming more evident as each day goes by", ahead of a much-anticipated speech by the Prime Minister on Brexit on Tuesday.

Salmond also accused May of an "increasing absurdity" over her stance on Europe, as he hit out at her refusal to back a separate bespoke deal with the EU for Scotland, amid the threat of a hard Brexit.

The former First Minister said there was an appetite for a second independence referendum and an "enormous enthusiasm" for Nicola Sturgeon's plan to protect Scotland's place in the European single market.

Sturgeon has demanded powers be devolved to Holyrood to allow Scotland to remain in the market even if the rest of the UK leaves, with responsibilities transferred over areas such as immigration, business regulation, and employment rights.

Salmond said the Scottish Government's demands for a separate deal with the EU was "unanswerable" after the EU's chief negotiator Michel Barnier stated he wanted a “special” relationship with the City of London once Britain has left the bloc.

His remarks came as May is set lay to out her plans for the UK's exit from the EU on Tuesday. She has faced intense political pressure to state more details of her negotiating priorities before she triggers Article 50, the formal process for leaving the EU.

May's speech also comes ahead of the judgment expected this month in the UK Government's appeal against the High Court ruling that MPs must be consulted before the withdrawal process begins.

Salmond welcomed reports that Barnier reportedly told MEPs that he wanted a “special” relationship between the 27 remaining EU countries and Britain’s financial centre after Brexit.

He said: "It indicates the farce behind the position of the UK Government. Theresa May, at the last count, was considering a special deal for Northern Ireland, the Channel Islands and the car industry in Sunderland. Now there's an indication there could be a special deal for the City of London.

"That would all make it impossible to resist the Scottish Government's argument that Scotland should be given special status."

Salmond welcomed a report published last week by the the House of Commons Committee for Exiting the EU that calls for the UK Government's Brexit plan to be published by mid-February in a white paper.

He said: "The increasing absurdity of her vacuous position on this was exposed with the parliamentary committee's demand for a white paper."

When asked whether he believed there was an appetite for a second independence referendum, Salmond said: "Yes I do."

He added: "Theresa May's speech is not going to cut it. The lack of stature for her position is becoming more evident as each day goes by.

"The Scottish Government's position is clearly unanswerable and is not one that can be just dismissed on Tuesday by Theresa May. There is enormous enthusiasm for the position of the Scottish Government."

Meanwhile, SNP MP Joanna Cherry, a member of the Commons Brexit committee, said Barnier's indication of a deal for the City of London boosted Scotland's case for a similar arrangement.

Cherry, the SNP's justice spokesperson at Westminster, said: "It's significant because it shows the EU is willing to look at different deals. If there is a political will for a deal it will happen."

Scotland's Brexit minister Michael Russell will this week warn Scots not to fall for the ‘fake news’ of a hard Tory Brexit being positive for Scotland.

A UK Government spokesperson, in response, said: "We are determined to get the the best possible deal for Scotland and all parts of the UK? as we leave the EU."