Climate-change protesters snarled traffic by blocking four London bridges on Friday, while other activists continued weeks of demonstrations targeting oil terminals across Britain.

Cars and red double-decker buses backed up along roads as hundreds of Extinction Rebellion activists occupied London's Waterloo, Blackfriars, Lambeth and Westminster bridges, calling for an end to new fossil fuel investments.

The Metropolitan Police force said "pockets of protest" were causing delays and disruption across central London.

The demonstrations are part of a growing climate action movement that has also seen the group Insulate Britain obstruct highways and roads to press demands that the government fund more energy-efficient homes.

In response, the Conservative government has introduced measures to curb disruptive protests, a move that has sparked debate about freedom of speech.

On Friday the government praised oil companies for obtaining court orders to stop demonstrators who have been blocking oil depots.

More than 600 people have been arrested over the past two weeks after environmental activists climbed atop oil tankers, padlocked themselves to structures and blocked roads at oil depots across the U.K. The group Just Stop Oil, which is affiliated with Extinction Rebellion, is demanding the government stop any new oil and gas projects.

Energy Minister Greg Hands said that "while we value the right to peaceful protest, it is crucial that these do not cause disruption to people's everyday lives." He said several firms have been granted injunctions that limit protesters' actions and access to sites.

Protests continued Friday at sites in southeast and central England despite the injunctions, with dozens of arrests.