A NEW constitutional “power grab” row is set to erupt between Westminster and Holyrood over the UK Government’s Trade Bill.

It comes amid a bitter stand-off between the Conservative Government and devolved administrations in Edinburgh and Cardiff over the flagship EU Withdrawal Bill, which led to Scotland and Wales bringing in their own continuity legislation yesterday.

LETTER: We call on MSPs to withhold consent for the UK Trade Bill

They said the action was required to protect powers they were given under the devolution settlements.

Now the prospect of a new battle has emerged with pressure being heaped on MSPs to reject the Trade Bill, which Holyrood is being asked to consent to by the UK Government.

More than 20 organisations and 800 people have put their names to an open letter, published in The National today, urging MSPs to oppose the legislation. They include trade unions as well as environmental and international social justice groups.

READ MORE: The UK is only experiencing the beginning of the Brexit chaos

Last month Scottish Brexit Minister Michael Russell wrote to Holyrood’s finance and constitution committee, currently examining the Bill, to recommend it does not consent to it. He made similar arguments about power grab concerns cited by the Scottish Government in opposing the EU Withdrawal Bill.

“The Scottish Government is not able to recommend that Parliament give its consent to the Bill, as it is currently drafted,” he said in a letter to the committee’s convener Bruce Crawford last month. “As with the European Union (Withdrawal) Bill, a particular problem with the Trade Bill is its failure to reflect the principles of devolution. In particular, the Trade Bill places constraints on the Scottish ministers’ ability to act on all devolved matters by placing restrictions on how they can exercise the powers in clauses 1 and 2 to make regulations.”

READ MORE: Brexit talks akin to 'pulling teeth', former Irish leader tells Alex Salmond

The open letter is due to be handed into MSPs on the finance and constitution committee at Holyrood today.

It appeals to its members to withhold their consent unless the Bill is amended to allow provision for MSPs, and MPs, to have a say in post-Brexit trade deals and warns of lowering standards in a host of areas should the Bill pass unamended.

It states: “The Trade Bill currently contains no provisions for allowing parliamentary scrutiny, by Westminster or Holyrood, of existing or future trade deals. There is a clear democratic deficit, with the UK Government effectively able to set up, develop and finalise trade deals with no oversight or accountability.”

READ MORE: Lord Advocate hits back at Holyrood's Presiding Officer over Brexit Bill

Signatories to the letter include social justice campaign organisation Global Justice Now, which took a key role in opposing the TTIP trade deal between the US and EU, the environmental charity Friends of the Earth Scotland, as well as leading trade unions Unison and Unite.

Liz Murray, head of Scottish campaigns for Global Justice Now, said: “In its Trade Bill, the UK Government is proposing being able to make post-Brexit trade deals behind closed doors. Given that it was one of the biggest cheerleaders for the controversial EU-US trade deal TTIP, and is likely to base future trade deals on that model, then it’s absolutely vital that things are brought out into the open and that the public and parliamentarians have a say – including here in Scotland. We know that these trade deals will have impacts here in Scotland: on our NHS, our food safety standards and our laws to protect workers’ rights and the environment. So there’s a clear democratic deficit here. Unless the Trade Bill is amended to fix this then we urge the Scottish Parliament to withhold its consent for the Bill – and that’s what our open letter is calling on MSPs to do.”

Simon Macfarlane, of Unison Scotland, said: “Given that Prime Minister Theresa May has refused to rule out giving US companies access to NHS contracts as part of a future trade deal with the US, we believe it’s absolutely vital that these kind of post-Brexit trade deals are given full parliamentary scrutiny so that all our public services are protected.”

Scotland currently has a ban on growing GM crops, using its autonomy under EU law. SNP ministers would also want an EU ban on chlorinated chicken imports.

But after Brexit, there are fears the Conservative Government at Westminster may seek to allow GM crops, lower environmental protections and food standards, and allow unrestricted US agricultural imports in a bid to help strike a UK/US trade deal.