Brexit talks resume Thursday with no indication that a breakthrough is in reach: While both sides are hoping for an agreement by the end of the year, the Europeans are striking a cautious tone. Prime Minister Theresa May’s Brexit advisor Oliver Robbins has been in Brussels this week and speaking to the EU team in private before the official start of talks, according to people familiar with the situation. Irish Prime Minister Leo Varadkar told lawmakers in Dublin on Wednesday he expects a breakthrough in December, which would allow negotiations at last to move on to trade. But EU envoys in Brussels were more cautious Wednesday, as diplomats reiterated their concerns about the risks posed by the U.K.’s political crisis at home, according to a person familiar with the discussion. Countries including Germany asked negotiators not to rush into preparing documents for trade talks, to avoid sending the wrong signals to the U.K. To break the deadlock, the U.K. has to make an offer on the Brexit divorce bill that’s good enough to satisfy EU leaders—who have the final say on whether talks can move on to the crucial issue of trade. Time is running out to clinch a deal before the U.K. tumbles out of the bloc in March 2019. While the EU doesn’t expect a figure from the British side, they do want more detail as to where the U.K. thinks it’s on the hook.  ‘Line by Line’ The European side reckons the U.K. owes about 60 billion euros ($70 billion). So far the U.K. has agreed to pay about a third of that and is going through the other demands “line by line,” May says. Brexit Secretary David Davis has hinted that he could go further, though it’s a sensitive issue at home: voters were told departure from the bloc would bring financial dividends, not bills. EU diplomats have begun work on two versions of draft summit conclusions for the gathering of European leaders in December—one for the possibility of a breakthrough and another one for continuing stalemate. In the run-up to this week’s talks, Davis has been on a tour of European capitals to try to win allies, but there’s been no indication so far that he has put anything new on the table. On Wednesday he met Polish Deputy Foreign Minister Konrad Szymanski, who said that if Britain offers a clearer picture of what it wants from the transition—the arrangement Britain wants to put in place to smooth the exit—that could help break the deadlock on the bill. More than year on from the Brexit referendum, there’s barely been progress toward the exit. The issue that was meant to be easy—the rights of EU citizens in the U.K. and Brits in Europe—is still to be resolved, even as both sides say advances have been made. Daunting Tasks The U.K. hasn’t set out a clear vision of what it wants from the future relationship, beyond saying it seeks a deep and special partnership. In recent weeks the British position on what it wants from the transition arrangement has become less clear. The EU side meanwhile has refused to budge, sticking to its demands that first the divorce must be settled, and only then can the future be discussed. May is struggling to hold her government together and to forge a Brexit policy that her divided cabinet, and the Parliament she controls by a slim margin, can back. Sex scandals continue to threaten her fragile administration, amid speculation she may not survive long enough to deliver Brexit. The Times of London reported that EU leaders are preparing for May’s fall. A further complication could arise from the hard-line stance of the veto-wielding European Parliament. “We don’t recognize reports suggesting that a deal on citizens’ rights is almost finalized,” the chamber’s Brexit Steering Group said in a statement Wednesday. “There are still major issues that have to be resolved.” German government advisers on Wednesday raised the prospect of an extension to the negotiation process, saying talks would likely drag on beyond the two years envisaged in EU rules. A one-time extension should be granted, the country’s Council of Economic Experts said. Looking ahead to December, there’s hope on both sides and a desire to move talks on to trade, according to a European official who asked not to be identified. A summit in October ended without concrete progress but with warm words from leaders including German Chancellor Angela Merkel that a breakthrough was possible by year-end if both sides made an effort. “I am more optimistic than I was in the weeks before the October summit,” Varadkar told his parliament in Dublin on Wednesday.