BERLIN, Germany (AP) — The three main candidates to become the new head of German Chancellor Angela Merkel’s party have agreed that the decision should be made in mid-January, a party official said Saturday as leading contenders scrambled to end an increasingly bitter dispute.

The centre-right Christian Democratic Union has been in leadership limbo since current chairwoman Annegret Kramp-Karrenbauer, who succeeded Merkel in 2018, announced in February that she wouldn’t run for chancellor next year and would relinquish her party role.

A special April convention to choose a successor had to be scrapped because of the coronavirus pandemic. The decision was put off until a regular party convention scheduled for December 4, which the party leadership in turn scrapped Monday because virus infections have risen sharply again and Germany’s states have imposed new restrictions.

The cancelation brought into the open rifts between the contenders for the CDU leadership. Merkel, 66, has vowed not to seek a fifth term as chancellor, and the next party chair would be in position to run in the election to succeed her, although that isn’t automatic. The party currently has a strong lead in polls.

The main candidates to become the leader of the Christian Democrats are Friedrich Merz, 64, a conservative former leader of the party’s parliamentary group who spent years away from front-line politics; Armin Laschet, 59, the more liberal governor of North Rhine-Westphalia state; and Norbert Roettgen, 55, who chairs parliament’s foreign affairs committee.

Laschet favoured delaying the December convention. Merz, a one-time rival of Merkel’s who polls suggest is a favourite among the party’s grassroots, pressed for a vote to go ahead and charged that “parts of the party establishment” were trying to prevent him from becoming leader. He alleged that Laschet had signalled he needed “more time to improve his performance.”

The open disagreement was an unusual spectacle for the traditionally disciplined party, and it alarmed many prominent members. In comments to the weekly news magazine Der Spiegel on Saturday, Kramp-Karrenbauer called on the contenders not to conduct “discussions that damage the CDU as a whole”.

On Saturday evening, CDU general secretary Paul Ziemiak tweeted that the three candidates agreed to seek a party convention in mid-January to decide the issue — held in person if possible, and if not, with an online vote backed by a written ballot. Details will be decided in mid-December.

Ziemiak welcomed what he called a “strong sign of unity”.