BERLIN (Reuters) - Former German Finance Minister Wolfgang Schaeuble urged Chancellor Angela Merkel’s conservatives and Social Democrats on Saturday to quickly form a new government, but said he could not rule out a minority government if no deal is reached.

FILE PHOTO: Wolfgang Schaeuble of CDU, president of the Bundestag, German lower house of Parliament, is seen during a session of the Bundestag in Berlin, Germany, November 21, 2017. REUTERS/Axel Schmidt

Germany’s constitution does not favor a minority government but that remains an option, Schaeuble, a leading conservative who is now president of the Bundestag (lower house of parliament), told Berlin’s Tagesspiegel newspaper.

A deal between Merkel’s conservative camp (Union) and the center-left Social Democrats (SPD) is her best chance of securing a fourth term in office. But Merkel’s possible coalition partners are angling for concessions beforehand.

“A stable alliance between the Union and the SPD would be preferable,” Schaeuble said, adding that the chancellor could still form a minority government. “It would work one way or another,” he said when asked about that possibility.

Coalition talks should be completed “sooner rather than later,” he said, noting that the Bundestag was not fully capable of action until a government had been formed.

He noted that President Frank-Walter Steinmeier - who stepped in after Merkel’s talks with two smaller parties collapsed in November - had urged conservatives and the SPD to reach an agreement as soon as possible, and said Merkel and other politicians had supported that call.

Horst Seehofer, head of the CSU Bavarian sister party of Merkel’s conservatives, told DPA news agency a new “grand coalition” should be completed by Easter, which falls on April 1 in 2018.

Seehofer said he favored new elections over a minority government.

MERKEL’S STATURE WANING

A new poll conducted for Die Welt newspaper showed waning support for Merkel, who has been unable to form a new government three months after national elections. Her talks on forming a three-way coalition with the environmentalist Greens and the pro-business Free Democrats fell apart in November.

The poll showed that 46 percent wished Merkel would resign immediately as chancellor, with an additional 17 percent of those polled saying that she should quit if the coalition talks with the SPD also failed.

A separate poll conducted for Bild am Sonntag newspaper showed that 33 percent of Germans trusted Defense Minister Ursula von der Leyen to replace Merkel as leader of the Christian Democratic Union (CDU), followed by Interior Minister Thomas de Maiziere with 32 percent, if Merkel resigned.

FDP leader Christian Lindner told Bild am Sonntag newspaper that Germany’s political system was in the middle of a major transition, and many conservatives also favored a “renewal.”

Simone Peter, one of the co-leaders of the Greens, told the Funke newspaper chain she hoped a stable new government could be formed, and that new elections should be “the absolute last resort.” She said the Greens remained open to dialogue if Merkel’s talks with the SPD failed.

SPD members on Saturday rejected a call by the CSU to raise military spending that could strain exploratory talks about a coalition that are due to start on Jan. 7.

A draft CSU resolution seen by Reuters on Friday called for military spending to reach NATO’s target of two percent of economic output and rejected the idea of an “ever closer” European Union backed by SPD leader Martin Schulz.

SPD deputy leader Ralf Stegner said on Twitter that his party was focused on spending for families, education, health care and education.