Climate activist Greta Thunberg hits out at the 'beautiful words' of politicans

Politicians are offering only "beautiful words" in the face of climate change, Swedish teenager Greta Thunberg has told her supporters in the UK.

Swedish environmentalist Greta Thunberg speaks to demonstrators during a Bristol Youth Strike 4 Climate (BYS4C) march in Bristol, England. Source: Getty Images Europe

The global establishment is offering only "beautiful words" to mitigate the climate crisis, Swedish teenager Greta Thunberg has told British supporters.

"How do we want to be remembered?" Thunberg, 17, asked thousands of activists at a Fridays for Future climate change protest in the southwestern English city of Bristol.

Swedish climate activist Greta Thunberg (C) takes part in a "Youth Strike 4 Climate" protest in Bristol, south west England. Source: AFP

"This is an emergency... and it will get worse," she told the crowd, which police estimated at more than 20,000.

"This emergency is being completely ignored by the politicians, the media and those in power," Thunberg said in a brief speech before the protesters marched through the city.

"Basically, nothing is being done to halt this crisis despite all the beautiful words and promises from our elected officials," she said.

"So what did you do during this crucial time?" Thunberg added.

"I will not be silenced when the world is on fire."