Scottish Secretary David Mundell said the draft Brexit agreement was “encouraging” but suggested the details could yet stymie agreement.
The Tory Cabinet Secretary said colleagues needed to “reflect on the detail”, understood to be referring to the latest technical details of the Northern Irish backstop.
Mr Mundell was heading into talks between the devolved UK nations chaired by de facto Deputy Prime Minister David Lidington as No 10 confirmed a draft Brexit deal would be laid in front of the Cabinet on Wednesday.
On his way into the joint ministerial council (JMC) at the Cabinet Office, Mr Mundell said: “I think it’s encouraging there’s a potential agreement.
“Obviously members of the Cabinet are going to have the opportunity to look at that in detail this evening and there will be a special Cabinet meeting tomorrow to reflect on what’s in that documentation.
“So I’m encouraged, but we need to reflect on that detail and see what’s there and hopefully be in a position to take forward a deal.
“That’s what the Government has been working for all this time, to get a deal, and negotiators have worked incredibly hard to get us to this point, but we have to reflect on the detail and consider at Cabinet tomorrow.”
On his way into the JMC, Scottish Brexit Secretary Michael Russell warned the threat of no-deal Brexit would not go away even if there was a deal struck.
He said: “I don’t know what we will hear from David Lidington and Dominic Raab, but quite clearly they’re here to discuss a range of issues including what progress they’re making, and particularly to get some information on that.
“It’s not good enough, with respect, to read it in the newspapers.
“We need to know what’s being done and we need to know what is being done in our name.
“Myself and the Welsh representative, Mark Drakeford, will be making that point forcibly here today as well as the point about the issue of no-deal.
“Whatever is resolved, that threat will not go away, given there are at least three more years of negotiations if there is a deal, and under those circumstances we will want to know what preparations there are for that.”
Mr Russell had called for the UK Government to reveal documents to ministers in the devolved administrations, and not just the UK Government, ahead of the meeting.
The Press Association understands the Scottish Government has so far only had information about the draft deal via back channels.