Fresh talks are due to take place in a bid to break the deadlock between Westminster and Holyrood over crucial Brexit legislation.
Cabinet Office Minister David Lidington will meet senior figures from the devolved administrations in Scotland and Wales to discuss their concerns that the European Union (Withdrawal) Bill represents a "power grab" by UK ministers.
Scottish Brexit Minister Mike Russell pledged to be "constructive" in the negotiations - but also made clear the Scottish Government would not sign up to any deal that they believe will "undermine the devolution settlement".
The row between the UK Government and the devolved administrations centres on where powers will lie once they are returned from Brussels post-Brexit.
As no deal on this has yet been agreed, the Scottish Government has controversially brought forward its own version of the EU Withdrawal Bill - which is designed to transpose European law into UK law in time for Brexit.
But Mr Lidington has urged the devolved administrations to "respond positively" to proposals from the UK Government and reach an agreement which would allow Edinburgh and Cardiff to give their formal consent to the legislation.
Speaking ahead of the talks in London, Mr Russell said: "We are going into this meeting seeking to reach an agreement on amendments to the EU Withdrawal Bill.
"But, in common with the Welsh Government, we simply cannot accept any proposal that would undermine the devolution settlement.
"The fundamental principle at stake is that any proposed change to devolved powers simply must have the agreement of the Scottish Parliament, as must any future legislation in the areas where UK-wide frameworks are under discussion."
He continued: "In the absence of an agreement to date, we are continuing to pursue our own Continuity Bill, which was approved overwhelmingly at Stage 1 by the Scottish Parliament yesterday.
"This is not a course of action we wanted to take, but it is one we have been compelled to pursue in order to protect devolution.
"We continue to believe, in line with the clear majority of people in Scotland, that continuing EU membership is in our best interests, but we will be constructive in today's meeting in seeking to show the UK Government that we can both protect devolution and prepare Scotland's and the UK's laws properly in the event of Brexit."
Meanwhile Mr Lidington stressed: "The Government is committed to exiting the EU in a way that provides certainty for businesses and families in all parts of the UK.
"We have been working hard to find an agreed way forward that fully respects and strengthens the devolution settlements and that also protects the UK's common market.
"We have listened to the concerns of the devolved governments and have put forward a proposal that would achieve that.
"It represents a considerable move by the UK Government that will see significantly more devolved powers.
"We now urge the devolved administrations to respond positively and reach agreement on this basis."