Merkel expects race to be “more difficult than any before” as she announces re-election bid after 11 years in office.

German Chancellor Angela Merkel has announced her intention to seek a fourth term next year despite losing support over her refugee policy.

Merkel, who has already served 11 years as chancellor, said on Sunday that she was expecting the upcoming general election, probably in September 2017, to be “more difficult than any before”.

“I thought about this for an endlessly long time. The decision [to run] for a fourth term is – after 11 years in office – anything but trivial,” she said after a meeting of senior members of her Christian Democrats.

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Merkel is widely seen as a stabilising force in Europe amid uncertainty after Britain’s vote to leave the European Union, and as a bastion of western liberal values after the election of Donald Trump as the next US president.

However, her decision last year to open Germany’s borders to about one million refugees, mostly from war zones in the Middle East, angered many voters at home and dented her ratings.

The 62-year-old conservative said she faced “challenges from all sides”, stressing that pressure from the right was particularly strong.

“We have a strong polarisation in our society,” she said.

The nationalist Alterative for Germany, or AfD, could prove one of the biggest stumbling blocks to her re-election.

The populist party, which is now represented in 10 state parliaments, has aggressively campaigned against Merkel’s decision to welcome so many refugees into Germany last year.

In elections in the eastern state of Mecklenburg-Western Pomerania earlier this year, Merkel’s CDU party came third behind the Alliance for Germany.

According to recent polls, the AfD would win about 10 percent of the vote if general elections were to be held now.

An exact date has not yet been set for the elections, but they will take place sometime between August 23 and October 22.

‘Pillar of stability’

A physicist by training, Merkel became chancellor in 2005. She is the first leader of a reunited Germany to have grown up under communism in the former East Germany.

If she wins next year and serves the entire four-year term, Merkel would match her one-time mentor Helmut Kohl’s post-war record of 16 years in office.

Nearly 60 percent of Germans surveyed in a recent poll said they wanted Merkel to run for office again, said Manfred Guellner, the head of the Forsa polling agency.

“In these difficult times, Merkel is a pillar of stability,” Guellner told The Associated Press news agency. “People have the feeling she represents German interests well abroad.”

While she has never been described as a visionary or earned much praise for stirring speeches, Merkel has won respect for being tough and shrewd in doggedly tackling problems.

Since becoming chancellor, she has dealt with several international crises, including the eurozone debt crisis in 2008-09, for which she brokered compromises among fractious European Union leaders.

She has been a strong advocate of efforts to combat climate change, and in 2011 abruptly accelerated the shutdown of Germany’s nuclear power plants following the meltdowns at Japan’s tsunami-hit Fukushima plant.

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Unresolved diplomatic challenges include Europe’s relationship with Russia, the future of Ukraine, autocratic developments in Turkey, the ongoing war in Syria and negotiations over Britain’s exit from the EU.

Al Jazeera’s Dominic Kane, reporting from Berlin, said Merkel will stress to voters that her steady hand over the past decade is needed on the reins of Europe’s economic powerhouse.

“From her perspective this election will be about showing to Germans why it’s so important they vote for somebody they can recognise as being a leader both in their country, but also someone the world sees as a person of real stature – who has been in charge of Germany, who has played such a central role in Europe, and indeed across the world,” Kane said.