German president says won't serve a second term in headache for Merkel

German President Joachim Gauck gives a press statement at the presidential residence Bellevue Palace in Berlin, Germany, June 6, 2016. REUTERS/Hannibal Hanschke

BERLIN (Reuters) - German President Joachim Gauck said on Monday he would not serve a second five-year term, a decision that could trigger a battle between the parties in Chancellor Angela Merkel's ruling coalition over who should succeed him.

Although the position of president is largely ceremonial in Germany, the selection of the last two heads of state has caused problems for Merkel and it risks dividing her government in the run-up to the next federal election in 2017.