Swedish teen activist Greta Thunberg has arrived at a port in Portugal after crossing the Atlantic in a catamaran to attend a UN climate change summit in Madrid.

The 16-year-old has become the face of young people's demands for climate action and made a point of making the journey back from September's New York climate summit by sea rather than by plane.

She had expected to be heading for Chile, but the South American nation passed the hosting of the COP25 summit meeting to Spain following violent anti-government protests.

Greta set sail on the 14m La Vagabonde catamaran on 13 November from Hampton, Virginia, to return to Europe.

She, along with British navigator Nikki Henderson and the Australian family who own the vessel, have arrived in Portugal's capital Lisbon after a voyage of more than 5,500km.

Greta is scheduled to hold media interviews then take an overnight train to Madrid, Portuguese sources said.

The climate summit, which opened yesterday and runs to 13 December, brings together representatives of some 200 signatory nations to the 2015 Paris accord.


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