German President Joachim Gauck announced on Monday his decision against running for a second five-year term due to advancing age, presenting Chancellor Angela Merkel with another political headache ahead of next year's election.

The 76-year-old former pastor and human rights advocate from the former communist East Germany has held the largely ceremonial post of president since March 2012.

"This decision was not easy for me," Gauck said in a statement at his residence, Berlin's Bellevue Palace. "I would not like to assume that I can guarantee the energy and vitality for another period of five years [as president]."

Gauck added that a change in high office was part of the normal process of democracy, but said "the years between 77 and 82 are different than those that I'm in right now."

Even before his formal announcement, German media had begun speculating about his possible successor. The daily Bild reported at the weekend that he planned to step down from the post.

The list of possible candidates include: parliamentary speaker Norbert Lammert; Finance Minister Wolfgang Schaeuble; Foreign Minister Frank-Walter Steinmeier; and the head of Germany's top court, Andreas Vosskuhle.

During his four years as head of state, Gauck has been seen as restoring a sense of dignity and moral authority to the presidency after his two predecessors left office before the end of their terms.

"Gauck has returned the high moral integrity to the Office of the President,” German Justice Minister Heiko Maas.

His comments were echoed by Horst Seehofer, a key figure in Merkel's coalition government, who said Gauck had "given people a sense of orientation and brought them together."

The president is elected in secret ballot by the so-called Federal Convention, which altogether comprises more than 1,000 members.

This includes members of the lower house of parliament, the Bundestag, as well as a raft of delegates chosen by the nation's 16 states. This often includes celebrities and national figures.

However, the vote for a new president is also seen as a test of the political authority of the chancellor of the day. That could mean  another test for Merkel, who has recently faced a barrage of criticism from within her own conservative political bloc for her handling of the nation's refugee crisis.

Merkel's two previous nominations, Horst Koehler and Christian Wulff, both resigned before their terms were out and as a result were seen as a political embarrassment to the chancellor.

Koehler stepped down following comments he'd made about Germany's military role in Afghanistan, while Wulff resigned amid allegations of a corruption scandal.

Leading political figures had spoken out in favour of Gauck seeking a second term so as to avoid complicating the build-up to the national election set for September 2017. The presidential election is expected in February.

Merkel, who is due to meet Gauck later Monday for routine talks, now has the choice of either deciding on a candidate from the ranks of her Christian Democrats (CDU) and their Bavarian-based Christian Social Union (CSU) allies, or seeking out a replacement who has much broader political appeal.

Gauck was elected to the office without any party affiliation.

But with an election on the horizon it might be difficult for Merkel to secure the backing of the major parliamentary parties for a common candidate.

The hard-left opposition Die Linke has already called on the left-leaning Social Democrats and the environmental Greens to join together behind one candidate.

Latest news

Syrian opposition rules out future role for President al-Assad

The Syrian opposition said Friday it would not accept any role for President Bashar al-Assad in the future of the war-torn country, reacting to a recent US shift saying that removing al-Assad is no longer a priority for Washington.

Russian Army integrates breakaway forces of Georgian province

Parts of the small fighting forces of the Georgian breakaway province of South Ossetia have been placed under Russian military control, Russian Defence Minister Sergei Shoigu said on Friday.

Czech Republic's Pilsner Urquell beer is now Japanese

Japanese brewing company Asahi completed its takeover of the Czech brewery Pilsner Urquell on Friday, Asahi said in a statement.

Judge approves 25-million-dollar settlement of Trump University case

A US district judge on Friday approved a 25-million-dollar settlement of lawsuits and state fraud allegations against Trump University, the US president's now-defunct business venture.

Former Thai premier Thaksin to junta on reconciliation: 'Cut me out'

Former Thai prime minister Thaksin Shinawatra on Friday announced that he is not interested in the junta-led reconciliation process, three days after the junta handed him a half-a-billion-dollar tax bill for his past business deal.

Dalic: We welcome possible deal between Agrokor and banks

The government welcomes the possibility of an agreement being concluded between the Agrokor food company and creditor banks, and the bill on vitally important companies is not a fallback plan but the result of the government's care for the overall economic and financial stability of Croatia, Deputy Prime Minister and Minister of Economy Martina Dalic told a press conference in Zagreb on Friday.

Croatia, China sign action plan for cooperation in agriculture

The Croatian and Chinese ministries of agriculture on Friday signed an action plan for cooperation in the field of agriculture for the period 2017-2018, the Croatian ministry said in a statement.

ZSE indices up, Agrokor shares in focus of investor interest

The Zagreb Stock Exchange (ZSE) indices on Friday rose by more than 1.8%, with stocks of the Agrokor food and retail concern being in the focus of investor interest again.

Berlin police defend handling of Berlin market attacker

Berlin police defended themselves on Friday against accusations that they stopped surveillance on Berlin Christmas market attacker despite knowing in June 2016 he was dangerous.

Croatia, creditors tailor emergency measures to save tottering giant

Croatia's tottering retail and food giant Agrokor reached an agreement with its creditors, putting its debts standby and allowing it to continue working during emergency restructuring, the Croatian branch of Austria's Erste Bank said Friday.

Agrokor's creditors say standstill agreement to go into force today

A standstill agreement regarding the Agrokor concern's existing financial obligations to banks will take effect on Friday, additional capital will be injected into the concern in the coming days and the concern will be actively restructured, which includes a change of its management, it was said on Friday after a meeting between Agrokor's suppliers and creditor banks.

Palestinians, UN slam Israel's new settlement plan

Palestinians, Israeli activists and the UN lambasted the government of Israeli Prime Minister Benjamin Netanyahu on Friday, a day after it gave the go-ahead for the first new West Bank settlement in a quarter of a century.

South Sudan rebels release three abducted foreign oil workers

South Sudanese rebels have released three foreign engineers they abducted in early March in the oil-rich Upper Nile region, Foreign Affairs Ministry official Mawein Makol Arik said on Friday.

Turkish opposition: Imprisoned party chief has gone on hunger strike

The head of Turkey's pro-Kurdish opposition party has launched a hunger strike from prison.

European leagues threaten Champions League schedule clashes

The European Professional Football Leagues (EPFL) on Friday threatened schedule clashes on Champions League matchdays in an ongoing dispute with the governing body UEFA.

Danish court revokes citizenship of IS volunteer

A Danish appellate court on Friday stripped a man of his Danish citizenship for volunteering to fight for the extremist Islamic State in Syria.

Banks and Agrokor agree on key elements of standstill agreement

Member banks of the coordinating committee of financial creditors and representatives of the Agrokor food company have in principle agreed on key elements of a standstill agreement, which is expected to be signed later today, announcing changes in the company's management team, Erste Bank said in a statement on Friday afternoon.

Syrian man on trial in Sweden; mosque attack labelled terrorism

A Syrian man went on trial Friday in the southern Swedish city of Malmo, charged with terrorism and arson after an attack last year on a building used as an assembly hall by Shiite Muslims.