BERLIN (AP) — The German government on Monday urged a group of young climate activists staging a hunger strike outside the chancellery not to endanger their health.

Several of the activists have threatened to stop consuming liquids, too, unless the three leading candidates to succeed Angela Merkel as chancellor agree to meet them by Thursday evening.

“Actions that endanger health, such as this hunger strike, such as the threat not to drink anymore, must be a cause for concern about the young people taking part,” said Merkel's spokesman, Steffen Seibert.

Several activists have received medical treatment after collapsing during the hunger strike, which began Aug. 30.

Seibert said the government considers climate change to be “the central issue of our time," but declined to say whether Merkel planned to intervene.

Thousands of youth activists, including Swedish campaigner Greta Thunberg, are expected to take part in a climate protest in Berlin on Friday, two days before Germany elects a new parliament.

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