Environmental campaigners have blocked a busy city centre road in Cardiff to protest against climate change.

Extinction Rebellion protesters cut off traffic from using Castle street outside Cardiff Castle as part of their five-day “summer uprising” in several cities across the UK.

On Monday campaigners parked a large green boat outside the castle and held banners reading “Act Now” and “Climate Emergency” as commuters were subjected to delays during the morning rush hour.

Tents were also set up on grass in front of Cardiff City Hall, the home of the Welsh capital’s local government, as campaigners looked set to camp there ahead of more disruption in the coming days.

A leaflet handed out by campaigners said they were protesting “to prevent the breakdown of humanity’s life support system, the Earth”, and said they were calling for the the UK Government to create a “national assembly” to implement climate change solutions.

Stephen Lingwood, 37, from Extinction Rebellion Cardiff, said: “People are dying right now of climate chaos in places like India. It’s only going to get worse.

“We’re at the beginning of the sixth mass extinction and a climate genocide and the Government’s inaction is, in my view, criminally irresponsible.”

South Wales Police said they were working with Cardiff Council in order to minimise delays to public transport across the city, and advised motorists to consider alternative routes due to the road closure.

The Welsh Government was the first in the UK to declare a climate change emergency earlier this year, before similar declarations by the Scottish Government and MPs in the House of Commons.

Other Extinction Rebellion protests are being held in Bristol, Leeds, London and Glasgow.