The conservative union bloc said coalition talks scheduled for Wednesday could be endangered if Chancellor Gerhard Schröder does not agree to step aside.
Negotiations between the two big parties could end before they begin
The fight over the chancellorship is proving a major obstacle to easing the political deadlock in Germany ever since the inconclusive federal elections on Sept. 18.
Schröder, whose party has four fewer seats in parliament than the conservatives after the vote, has refused to concede defeat and his Social Democratic Party has said if wants him to lead, even as part of a "grand coalition" with the center-right.
This has not sat well with the conservatives, who have said Schröder's agreeing to step aside and making room for Angela Merkel as chancellor is a prerequisite to entering into substantive talks about forming a coalition of the two major parties.
"It is expected that the talks, after a brief session on Wednesday, will have to be broken off," a senior member of Angela Merkel's Christian Democrats (CDU) told Reuters on condition of anonymity.
In a telephone conference of the CDU leadership, there were serious doubts expressed whether or not the scheduled Wednesday talks could go ahead.
The parties are due to meet on Wednesday at 2:00 p.m. for a third round of exploratory talks.
Volker Kauder, secretary general of the CDU and a Merkel ally, said on Tuesday that it was time that the SPD recognized reality and that the German people are waiting for a government to be formed.
Who will be chancellor? It's still unclear.
"I call on the rational elements in the SPD to recognize our claim (to the chancellery) so that we can move ahead on the substance of these talks," he said on German public television.
On the other side, the SPD is wary of sacrificing Schröder before the talks begin, although party chief Franz Müntefering has indicated that the party is ready to move beyond the initial phase and begin serious negotiations. The SPD has insisted it be treated as an equal in any discussions and not as a junior partner. It is keen to win several prominent ministerial posts and to influence policy.
"Now (Schröder) is letting himself be used as a colorful gambling chip," said the conservative newspaper Die Welt in an editorial.
Right now, the posturing is in full swing and it is unclear who will blink first.