BERLIN • German Chancellor Angela Merkel is pushing ahead with discussions on forming a four-party government after all-night talks with potential coalition partners produced momentum without resolving key differences.

Seeking to avert a crisis that would threaten her fourth term, Dr Merkel and the bloc formed by her Christian Democrats (CDU) and Christian Social Union (CSU) reconvened yesterday with the Free Democrats (FDP) and Green party.

After the Chancellor initially set an informal Thursday deadline to wrap up a month of exploratory talks and move forward to concrete coalition negotiations, officials said several more days may be needed.

"It isn't easy," Dr Merkel told reporters in Berlin.

"We raised a host of very, very detailed topics in the exploratory talks, and so it's not going to be entirely straightforward to tie the loose ends together."

Discord over sharing financial risks in the euro area, cutting carbon emissions and limiting immigration has hamstrung Dr Merkel, Europe's longest-serving leader, who won a fourth term in September but is stuck with a caretaker government. Even a deal to move ahead now would be only an intermediate step, followed by detailed talks on a policy blueprint for the next four years.

The parties remain "far apart" on issues that include immigration, climate change, fiscal policy and internal security, senior FDP lawmaker Wolfgang Kubicki told ARD television yesterday.

"I'm struggling to see how we'll reach an agreement quickly," Mr Kubicki said. "There's always the suspicion that you're being taken advantage of, which is not a good basis for compromise."

Mr Volker Kauder, the head of the CDU/CSU parliamentary caucus, told reporters success was still possible.

"We've spent four weeks together in these exploratory talks," Mr Kauder said, shortly after talks resumed. "They must now come to a conclusion this weekend."

Germany's domestic conflicts, which reflect an increasingly splintered political landscape, are playing out on the global stage.

Dr Merkel has put euro-area policy on hold until there is a new government. At a United Nations climate conference in Bonn this week, she flagged Green-led demands for curbing coal as a point of dispute in coalition talks.

Limiting the appetite for conflict on all sides is the risk of a repeat election if the talks collapse.

Dr Merkel's bloc won in September with its lowest share of the vote since 1949, while the anti-immigration Alternative for Germany (AfD) party, which campaigned against Dr Merkel and the rest of the political establishment, entered Parliament with 12.6 per cent.

Commentators say all sides will want to avoid triggering snap polls that could end up bolstering the AfD.

Surveys suggest there is little appetite for a return to the ballot box, and some two-thirds of voters say they expect the coalition negotiations to succeed.

BLOOMBERG, AGENCE FRANCE-PRESSE