Chancellor Angela Merkel, who has ruled Germany since 2005, has decided to run for a fourth term and has started planning her 2017 re-election campaign, according to an unsourced report Saturday in Der Spiegel news magazine.

A spokeswoman for Merkel's Christian Democrat (CDU) party declined to comment on the report. The chancellor is on a hiking holiday in the Alps.

Merkel, who turned 61 in mid-July, has not made any public comments about whether she will run for a fourth term, although she did hint in a speech in Cologne last year she will stand again.