John Swinney has insisted the Scottish Government will have “nothing to do” with a suggested new nuclear power station – as he hit out at the “menacing” behaviour of the Scottish Secretary.

The First Minister reacted angrily after Alister Jack revealed he has instructed UK ministers to start planning work for a nuclear plant in Scotland.

That comes despite the longstanding opposition from the SNP to the construction of such facilities north of the border.

Mr Jack told a Lords committee on Wednesday he believes there will be a “unionist regime again in Holyrood” in 2026, and with the SNP out of power it will be possible to “move forward” with the construction plan.

Speaking about the prospect of a small nuclear reactor, Mr Jack said he has asked the UK energy minister to “plan for one in Scotland”.

But Mr Swinney told MSPs on Thursday that Mr Jack has “made no mention of this proposal to the Scottish Government” – which has powers over planning north of the border.

The First Minister added: “This is utterly and completely incompatible with good intergovernmental working and is illustrative of the damaging behaviour, the menacing behaviour, of the Secretary of State for Scotland.”

He was asked about Mr Jack’s comments by SNP backbencher Rona Mackay, who noted the UK minister’s suggestion came despite “opposition from the democratically-elected Scottish Government” to new nuclear power.

Speaking at First Minister’s Questions, Mr Swinney was clear: “The Scottish Government will not support new nuclear power stations in Scotland.”

He said his Government instead supports investment in “the renewable energy potential in Scotland”, adding “massive investments” in this sector could “bring jobs and opportunities to the Highlands and islands and deliver green, clean energy for the people of Scotland”.

Mr Swinney said: “That’s the policy agenda of this Government and we will have nothing to do with nuclear power.”