PA Media

Greta Thunberg is due to address thousands of people in Bristol

Road closures are in place across central Bristol ahead of a climate strike march by Greta Thunberg.

The Swedish environmentalist will be at a Bristol Youth Strike 4 Climate (BYS4C) event on College Green, before joining the march through the city.

It is not clear how many people will attend but the event has "grown so large" usual safety measures may prove inadequate, police say.

BYS4C insists adequate safety measures are in place.

Avon and Somerset Police and Bristol City Council have warned of "major disruption" during the event, which is due to start at 11:00 GMT, but stressed they would be "working to ensure Bristol is open as usual".

Archie Richards

The first school strike in Bristol took place in February last year

More than 20 road closures are in operation from Broadmead and the Bearpit across to Hotwells, Brandon Hill and Park Street.

BYS4C said a similar protest last year attracted 15,000 and it was believed there could be many more people come to hear the 17-year-old speak.