INDEPENDENCE would impose “turbo-charged austerity” on Scotland, whereas Brexit offers an “opportunity” to bring more powers to Holyrood, Jeremy Corbyn has said.

On a visit to Glasgow, the Labour leader also dismissed Nicola Sturgeon’s proposal to keep Scotland in the EU single market, saying Brexit would be a UK-wide decision.

He said: “The question of single market access is and has to be a UK decision."

Mr Corbyn and Scottish Labour leader Kezia Dugdale are trying to establish a constitutional convention to devise a federal UK with an elected senate instead of a House of Lords.

After Theresa May announced on Tuesday that the UK would leave the single market in Brexit, the First Minister said a second independence referendum was “all but inevitable”

However Mr Corbyn said independence was not a straight alternative to Brexit, and Scotland could instead enjoy greater powers as a result of UK withdrawal from the EU - and idea recently advanced by former SNP cabinet secretary Alex Neil.

He said that since the 2014 referendum, the Nationalists’ economic arguments had weakened because of falling oil prices.

He said: “Of course Scotland has the talent and ability to run its own affairs. But I do not believe it would be the best option for the Scottish people.

“It would lead to turbo-charged austerity and a glaring hole in the money required to fund essential services, and would not be in the interests of the people of Scotland."

Ms Sturgeon called the claim as “rubbish”, Tweeting: “If Corbyn wasn't leading such a pitifully ineffective opposition the Tories wouldn't be getting away with half of what they are."

Mr Corbyn said independence would not tackle fundamental problems such as poverty, which required the redistribution of wealth, and power moving from the establishment to the people.

He repeatedly linking the SNP to what he called an “Edinburgh establishment”.

He said that after Brexit it was "vital" the UK Government gave more powers to Holyrood, the Welsh and Northern Ireland Assemblies and England's metropolitan mayors and councils.

“Brexit means we have to develop a long-term plan to build a fairer, more just country.”

He announced he would soon hold a summit with EU socialist leaders, as well as the CBI, to help influence foreign governments and parliaments to make “a Brexit that works for Britain".

Ms Dugdale said Brexit and a federal UK could mean Scotland getting more powers over workers’ rights and pay, and over tax powers, particularly VAT.

She said: “Our discussions should start with a simple principle. That what is not reserved is devolved, and that no powers should be re-reserved to Westminster.”

However the message was undermined by a row over Labour’s mayoral candidate in the West Midlands, Sion Simon, vowing to “call time” on the Barnett Formula which ensures higher per capita public spending in Scotland.

Scottish Tory whip John Lamont said Mr Corbyn’s visit had “blown up on the launchpad”.

He said: "As he was setting out another muddled plan for Scotland, his mayoral candidate was demanding that money be taken out of Scotland against his party's own policy.

"Mr Corbyn now must make it 100 per cent clear that Labour will stick by its promises to voters here about Scotland's funding."

Scottish Labour said: "This is a boomerang attack from the Tories. Around 100 Tory MPs tried to scrap the Barnett formula as recently as 2014. Labour is committed to the Barnett formula.”

SNP MSP Linda Fabiani said the day had been “an utter shambles for Labour - pledging to help the Tories drag Scotland out of the European single market one minute and demanding the end of the Barnett Formula and a cut to Scotland's cash the next.

"It truly shows how little power Kezia Dugdale wields in her own party.”