NICOLA Sturgeon has warned there must be “significantly more movement” from the UK government in the coming weeks or the plan to give Holyrood more powers could collapse.

In an interview with today's Andrew Marr Show, the First Minister says there is “a long distance still to travel” to secure a deal on the new Scotland Bill.

She said the Prime Minister "should be under no illusions" that she would block the legislation if her conditions were not met.

The last obstacle is the “fiscal framework” that must be agreed between Edinburgh and London on how new tax and spending powers will affect Scotland and the rest of the UK.

The bill would give MSPs control of income tax and new welfare powers, as well as a half of Scotland’s VAT receipts, offset by cuts to the £30m a year block grant currently funding Holyrood.

Although the changes should be relatively straightforward on day one, how the grant is adjusted over the following years is proving hugely complex and contentious.

Small shifts in the relative economies and populations of Scotland and the UK could result in major changes.

Under one of the scenarios being discussed, Scotland could quickly be hundreds of millions of pounds worse off.

After a series of meetings between the Scottish and UK governments, Finance Secretary John Swinney warned last week that the two sides remained a significant distance apart.

Without a deal by mid-February, there will not be enough time for MSPs to scrutinise the proposals and give their consent to the Scotland Bill becoming law before May’s election.

Sturgeon told Marr she wanted Scotland to have the new powers in the Bill, but would not approve it without the right fiscal framework in place.

She said the UK government’s starting position in the talks would have meant “systematic reductions” in the Scottish budget, regardless of the Scottish government’s decisions.

“That starting point was not something I as First Minister, with the job of standing up for Scotland could ever sign up to," Sturgeon said.

“Now time is short, the clock is ticking and there is a long distance still to travel. I hope we can get to a deal because I want to have these new powers. But as First Minister of this country, I will not sign up to anything that disadvantages in a systematic way the budget of the Scottish government.”

She said that if there was no deal, voters would question David Cameron’s intentions.

“If we can’t get a sensible, fair position in a fiscal framework, then I think people in Scotland will start to conclude that the Tories were never serious about giving Scotland extra power.”

She said her government would be “busting a gut” to strike a deal.

“But we will need to see significantly more movement from the UK government than we’ve seen so far, and if we don’t get that – I repeat again – I will not sign up to something that is unfair to Scotland.

“I’m not asking for any special favours for Scotland or for any special treatment, I’m simply asking for fairness and I won’t agree to something that doesn’t deliver that. And David Cameron should be under no illusions about that.”

She said she did not want to be in this position, and wanted a deal, but said voters would “draw their own conclusions” in May if there was still no agreement.

Swinney is due to give evidence to the Commons Scottish Affairs Select Committee on the fiscal framework issue in Perth tomorrow.

A UK government spokesman said: “Both governments want a deal that’s fair to Scotland and fair to all the taxpayers in the UK. We are focussed on getting that deal so Scotland can move on.”