British Prime Minister Theresa May will try to unblock Brexit negotiations over breakfast with her Irish counterpart Leo Varadkar on Friday as she battles to persuade European leaders to allow talks to move on to trade.

Varadkar is a key figure after the issue of the border between his Irish Republic and Northern Ireland in the U.K. burst into the center of discussions last week. It posed a new obstacle before future commercial and transition arrangements between Britain and the EU can be tackled.

May is flying to Gothenburg, Sweden, for an informal summit of European leaders and will meet Swedish premier Stefan Lofven before dinner on Thursday, May’s spokesman, James Slack, told reporters in London. She’ll then meet Varadkar, whose country exports about $40 billion of goods and services to the U.K., the following morning and sit down with EU President Donald Tusk later in the day.

Both the U.K. and EU want negotiations to switch from the separation issues to mapping out the future trading accord at a summit in Brussels in December. But talks must first make sufficient progress on the terms of the divorce.

Germany’s Angela Merkel is wary that pushing May too hard in Brexit talks could backfire by weakening her at home, according to a person familiar with the chancellor’s thinking. A replacement prime minister at this stage would likely be someone who takes a harder line with the EU and might potentially walk away from discussions.

The scale of the task became clearer last week when the EU circulated a blueprint demanding that Northern Ireland keep the rules of the bloc’s customs union and single market after Brexit.

The EU document ruled out any hard border along what will become the U.K.’s only land frontier with the remaining 27 member states when it leaves. The EU wants progress on the border issue before talks can focus on the transition period and future trade accord May is seeking to secure over the next 12 months.

“We want to make progress as quickly as possible and we want to move on to talking about the future relationship as quickly as possible,” Slack said when asked if the U.K. still believed the EU summit in December was a strict deadline for Brexit talks to progress.

Aside from the Irish border, Brexit talks are still stuck on the question of the so-called divorce bill: how much the U.K. will pay the EU when it leaves the bloc to honor its existing budget commitments.

Slack dismissed a report on Thursday that May is ready to offer an extra 20 billion pounds ($26.4 billion) on top of the 18 billion pounds she’s signaled the country will pay. He described the idea as “yet more speculation.”