Labour has accused the SNP of preparing to perform a U-turn on one of its flagship policies – nuclear power.

The SNP is vehemently opposed to the construction of a new generation of nuclear power plants in Scotland, but Labour has accused the party of preparing to signal that its stance has changed.

The attack has been rejected by the Scottish Government, which insists it remains opposed to a new generation of nuclear power stations and that it "will not happen in Scotland".

But in a speech this week Labour MP Tom Greatrex will accuse the SNP approach of being " chaotic and confused".

"However, as with a significant number of their policies, it would appear that Alex Salmond and the SNP leadership are preparing the ground for a U-turn," he will say.

"The signs are there if you look closely."

In the speech, at the TUC annual conference in Brighton, he will accuse the SNP of already shifting their position on nuclear power – from outright opposition to accepting the current role nuclear power plays in Scotland's energy mix.

He will add: "Do not be surprised if at some point in the next few years, the SNP's ideological opposition to nuclear power – that was evident only a few years ago – is swept under the carpet alongside previous policies on Nato, the monarchy and the currency in a separate Scotland, in the attempt to gain votes for its separatist agenda.

A Scottish Government spokesman said: "We have a long-standing opposition to the building of any new nuclear power stations, so that will not happen in Scotland.

"Nuclear is uninsurable in any real sense."

He added Scotland had been left with a radioactive waste legacy and estimated clean-up liabilities running at £45.1 billion.

"We have already made it clear that, subject to the relevant safety cases being made, the Scottish Government would not oppose operating life extension applications at Torness and Hunterston," he added.

The SNP leadership will attempt to overturn decades of opposition to membership of Nato at their annual conference next month.