German police say they have removed almost all climate activists from a German village that will be destroyed to allow the expansion of a coal mine.

Hundreds of officers cleared around 300 activists from Lützerath in an operation that began on Wednesday.

Police say they removed activists waiting in treehouses, a day after clashes broke out between both sides.

Two people were still holding out in an underground tunnel at the site in western Germany, police added.

"There are no further activists in the village of Lützerath," police said, adding that the buildings at the site had been cleared by Friday.

Police said that 35 "tree structures" and almost 30 wooden constructions had also been cleared away.

Climate activists said that the village and others nearby should not be demolished and the coal under them, near an open-cast brown coal mine, should be left in the ground.

Activists say burning the coal undermines Germany's efforts to reduce greenhouse gas emissions.

The village is owned by energy firm RWE, and the last resident moved out over a year ago.

Germany has promised to phase out coal-fired power by 2030, bringing forward the date from 2038, and Lützerath is expected to be the final village to be swallowed up by the Garzweiler lignite mine.

RWE said the coal under the village would be needed as early as this winter.

Tensions between police and climate protesters escalated on Saturday, with officers using water cannon and batons to disperse the activists.

Around 20 protesters were injured and taken to hospital, according to a medic with the activist group.

A police spokesman said around 70 officers had been injured since they began removing people from the site on Wednesday, with many of those officers injured during Saturday's clashes.

Swedish climate activist Greta Thunberg joined the protest and denounced "police violence" in removing climate activists from the site.

The climate organisers said around 35,000 protesters demonstrated on Saturday, while police officials put the figure at around 15,000.