Germany's second most powerful politician, Vice Chancellor Franz Muentefering, has announced that he will resign from office. His departure is likely to destabilize the already shaky power-sharing coalition between the country's two biggest parties.
The announcement that he would step down to care for his ailing wife, who he said last week had her fifth cancer operation, surprised the nation.
While Muentefering insisted in a news conference that the move was based entirely on "personal and private" motivations, he is leaving at a time of growing dysfunction in both the coalition led by German Chancellor Angela Merkel and his own party.
Muentefering helped form that coalition of traditional rivals of the center-left and center-right parties in negotiations after the close election two years ago. Since that time, he has often seemed like the glue that held it together, a stalwart of his left-wing Social Democratic Party but at the same time a confidant and trusted adviser to the conservative Merkel.
That has been an increasingly difficult balance to strike as Muentefering's party has shifted back toward its traditional base among voters on the left. That in turn has meant trying to roll back economic reforms made under the former chancellor -- and fellow Social Democrat -- Gerhard Schroeder, reforms that Muentefering helped enact and had recently tried to defend.
His departure will test Merkel's strength as a leader and consensus builder. While she remains very popular, with approval ratings hovering around 70 percent, her successes have only encouraged her coalition partners to differentiate themselves by challenging her policies that much more.
Following Muentefering's announcement on Tuesday, the Social Democrats swiftly named Foreign Minister Frank-Walter Steinmeier as his replacement as vice chancellor. Olaf Scholz, a leading member of parliament from the party, will take over Muentefering's other post as labor and social affairs minister. In contrast to Muentefering, Steinmeier has been sharply critical of Merkel on foreign policy recently. He is considered a possible challenger for chancellor in future elections.
"There are situations in life which are more important than politics," Merkel said on German TV. "I wish Franz Muentefering and his wife all the best. It is a pity that we cannot continue to work together."