DUBLIN - British Foreign Secretary Boris Johnson has called on Brussels to move on to post-Brexit trade talks to solve the Irish border issue , despite a warning from the EU that London still had work to do.

"The issues of the Northern Irish border and how it works are intellectually, intimately bound up with the questions of the customs union, the single market, Britain's relationship with those. "Those questions have been reserved by the (European) Commission for study in stage two of the negotiations. I think logically now is the time to proceed to stage two," Johnson said at a Dublin press conference with his Irish counterpart Simon Coveney.

Deciding the future of Britain's only land border with the European Union has been a top priority for Brussels, with all sides determined to avoid a return to a hard border between Northern Ireland and the Republic of Ireland . "We need to get on with this, but our view is that you can only really crack the problem in the context of a wider understanding of how the new customs arrangements are going to work," said Johnson.

The foreign minister's comments followed a warning from European Commission chief Jean-Claude Juncker, who on Friday said Britain must do "more work" before moving onto trade talks . "The clock is ticking. I hope that we will be able to come to an agreement as far as the divorce is concerned at the December council (summit) but work has still to be done," Juncker told reporters as he arrived at an EU summit in Gothenburg, Sweden. British Prime Minister Theresa May and her Brexit minister, David Davis, are also in Gothenburg for the European Social Summit.

After London failed to convince Brussels last month that sufficient progress had been made in divorce talks to move onto negotiating a future trade deal, Davis on Friday called on the EU to compromise. "Surprise, surprise: nothing comes for nothing in this world," he told the BBC in Gothenburg.

Various EU countries "can see there are big, big benefits in the future deal that we're talking about," he added.

Arriving at the summit, May said she hoped the EU would respond "positively" to British proposals so that negotiators could move on to discuss future ties. The prime minister is reportedly under pressure from Johnson and fellow Brexiteer Michael Gove, Britain's environment minister, who according to a leaked memo have tried to instruct her on how to run the exit negotiations.