Brexit secretary David Davis has said "considerable progress" has been made on important issues in his talks with the EU.
Davis and his counterpart, EU negotiator Michel Barnier, have today provided an update on the progress of negotiations.
The two sides have drafted principles on a common travel area to be created between the UK and Ireland, Davis said.
However, stumbling blocks remain, in particular over the role of the European Court of Justice (ECJ) and citizens' rights. Barnier said it could take months before sufficient progress had been made on withdrawal talks.
"You shouldn't be surprised that this takes time," Barnier said.
"I think that's its positive that Theresa May's speech made it possible to unblock the situation to some extent."
Davis said today that it was important that the two sides provided certainty over the rights of EU citizens, but that the UK should not allow the ECJ's rulings to take precedence over the UK courts.
Barnier said he wanted to secure the reciprocal rights of all citizens impacted by Brexit.
Barnier insisted that there had still not been sufficient progress on the financial settlement for talks to start on the future relationship between the EU and the UK.
"There is no possible link between that discussion [on the new relationship] and the separation issues and the commitments made in the past," Barnier said.
Davis was more possitive, although acknowledged: "We are not yet at the stage of specifying exactly what these commitments are. That will need to come later. Nevertheless, our negotiating teams have held very constructive discussions this week on detailed technical issues relating to that."
Davis added: "This work is necessary so that when the time comes we will be able to reach a political agreement. And discussions will continue."
In a joint statement, both the TUC and CBI urged negotiators to rule out a 'no deal' outcome, saying it could lead to continued uncertainty for the millions of EU citizens who live in the UK, and UK citizens who live in the rest of the EU.
Carolyn Fairbairn, Director-General of the CBI, and Frances O’Grady, General Secretary of the TUC, said: “After 15 months of human poker, the uncertainty facing four million European and UK citizens has become intolerable.
“It is a blight on the values of our nations. Millions of workers and thousands of firms are today united in their call to leaders on both sides to find an urgent solution. A clear guarantee of the right to remain for citizens in both the UK and EU27 is needed within weeks.
“EU citizens account for 10 per cent of registered doctors and four per cent of registered nurses across the UK. Millions more work in the public and private sectors delivering public services and making a vital contribution to our economy.
“They need to hear that they will be allowed to remain in the UK, whatever the eventual outcome of negotiations. Not only is this important for our economy, it is the right thing to do.
“Once agreed, this guarantee must be implemented independently of the rest of the negotiations to avoid the risk that ‘no deal’ in March 2019 leads to uncertainty and heartache for millions of people.”
Allie Renison, head of EU and trade policy at the Institute of Directors, welcomed "clear signs of progress", but warned both sides that "further flexibility is needed in this and other areas to move the discussions on, at a faster pace. The clock is still ticking".
Labour MP and leading supporter of Open Britain Heidi Alexander said: “Despite David Davis’ warm words, it is clear that not enough progress has been made in the talks and we remain significantly short of an agreement that will allow us to move on to negotiating Britain’s future relationship with the EU, which we were scheduled to do next month.
“Both the European Commission and the European Parliament have made clear today that real gaps remain between the two sides on all three major issues – on Northern Ireland; on citizens’ rights; and on payments... The longer we remain in negotiating limbo, the closer we get to a Brexit with a bad deal, or no deal at all, which would damage our economy and put jobs at risk.”
Liberal Democrat Brexit spokesperson Tom Brake MP was just as damning, saying Davis was "dangerously delusional about the level of progress that is being made"
“Brexit is a mess made in Westminster by the Conservatives," Brake added. "The time is ticking, on the deadline before we leave and on the last remaining shreds of this government's credibility. We need to stay in the single market and the customs union, and we need to give the people a vote on the final deal.”