Germany's centre-left Social Democrats (SPD) have agreed to talks with their former coalition partners, Chancellor Angela Merkel's centre-right Christian Democrats (CDU).
Delegates at a party conference in Berlin voted by a large majority in a show of hands to back a motion laying out the party's priorities in talks with the longtime chancellor's Christian Democrats.
SPD leader Martin Schulz, who initially said the party would go into Opposition after seeing its time in the last Merkel-led "grand coalition" rewarded with bruising losses at the polls, must now convince his party to reverse that decision.
"We do not have to rule at all costs".
Since the CDU's talks with the liberal FDP and the Greens fell down, the SPD has come under intense pressure to join coalition-building talks. "But we must not want to reign at any cost", he said in his speech.
"Only if Germany's role as the reform motor in the European Union is agreed in binding and concrete form in a coalition deal can this succeed - but not in the framework of parliamentary support agreements" for a minority government, he added. Merkel is facing the worst political crisis as no new government could be formed for the time being since the September 24 German federal elections.
The "grand coalition" of Germany's biggest parties is unpopular with many Social Democrats, and leader Martin Schulz has promised a membership ballot on any coalition deal.
The motion also includes a demand of ending a ban on some family reunions of asylum seekers, which is clearly opposed by CSU.
The approximately 600 SPD delegates are reluctant.
"The question isn't grand coalition or no grand coalition".
In an election later, Schulz was re-elected as SPD's party leader with a total of 81.9 percent of the vote, down from the 100 percent he received in March when he was elected as SPD Chairman.
Mrs Merkel said in response that her goal was better co-operation between countries, not a federal Europe.