A SCOTTISH MP has accused the UK Government of treating devolved nations "like children" after it threatened to repeal laws passed by the Welsh Parliament.

Whitehall announced its intention last week to overrule the Welsh Government's 2017 Trade Union Act, which bans agency staff from being used if public sector workers go on strike.

SNP MP Ronnie Cowan told The National the move was the latest evidence in Westminster interfering with devolved powers.

The Inverclyde politician said the Tories were running "roughshod" over the Holyrood and the Senned.

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Cowan said: "It’s further evidence of the UK Government interfering in the working of the devolved parliaments.

"There is a lack of respect for the developed powers within the cabinet office and inter-governmental relationships often involve Westminster riding roughshod of the devolved powers.

"I think it’s fair to say the devolved powers feel like they are treated like children. It’s a strange way to maintain a union of nations and certainly not one that treats us all as equals."

The threat by the UK Government, announced last Tuesday, led the Plaid Cymru leader to call for a referendum on Wales' future.

Calling the move "potentially devolution’s breaking point", Price urged a strong response from the Welsh Government, suggesting that the question of Wales' future in the United Kingdom should be put to the public in a referendum.

The National: Warnings over a UK 'power grab' in Wales echoes similar worries in ScotlandWarnings over a UK 'power grab' in Wales echoes similar worries in Scotland

"Westminster wants it to be a relationship where they are in control and our Senedd is subservient - where their Parliament is supreme and ours is subordinate," he said.

"[They] have shown their contempt not just for workers, not just for Wales, but for our democracy.

“This is not just one more in a long list of power grabs - it’s a turning point.

"It rolls back the rights of citizens, but also it denies those citizens' very right to decide their own future.

“There has to be a political response that will make Westminster sit up and listen. 

"A strongly worded letter from the Welsh Government is not going to work.

READ MORE: Mick Lynch calls for resistance to UK Government 'attack' on devolution

Welsh First Minister Mark Drakeford rejected the idea of a referendum in Wales, saying it should only happen if pro-independence parties win a majority in the Senedd.

The "power grab" announcement by the Tories coincided with the RMT rail strikes, which saw around 50,000 railway staff - from ticket collectors and cleaners to signallers and maintenance workers - walk out over pay cuts and working conditions.

Teachers, doctors, firefighters and postal workers are just some of those that could go out on strike in the coming weeks and months - again over pay cuts, jobs and working conditions - and bringing in agency staff would damage the ability of these workers to win their disputes.

In Wales, that practice is banned for public sector strikes. The UK Government wants to remove that ban - the latest in a series of measures which have contradicted Welsh government policy approaches and directly limited its lawmaking powers, such as the post-Brexit Internal Markets Act, and the Policing Act.