What is Extinction Rebellion and what does it want?

Campaign group Extinction Rebellion has begun what it describes as two weeks of climate protests in London.

It says its "Impossible Rebellion" will "target the root cause of the climate and ecological crisis".

Extinction Rebellion (XR for short) describes itself as an international "non-violent civil disobedience" movement.

It says life on Earth is in crisis and facing a mass extinction. It wants governments to declare a "climate and ecological emergency" and take immediate action.

Extinction Rebellion was launched in 2018 and organisers say it now has groups willing to take action in dozens of countries.

The group uses an hourglass inside a circle as its logo, to represent time running out for many species.

In the UK, Extinction Rebellion has three main demands:

Reducing CO2 emissions to almost zero in such a short period would be extremely ambitious.

Severe restrictions on flying would be needed. Diets would have to change, by drastically cutting back on meat and dairy.

And there would have to be a massive increase in renewable energy, along with many other radical changes.

But those involved with Extinction Rebellion say the future of the planet depends on it. "We have left it so late that we have to step up in a semi-miraculous way to deal with this situation," said co-founder Gail Bradbrook.

However, the group itself doesn't say exactly what the solutions to tackle climate change should be.

Instead, it wants the government to create a "citizens' assembly", made up of ordinary people. Its members would decide how to solve the climate crisis, with advice from experts.

On 23 August Extinction Rebellion supporters gathered in Trafalgar Square, to demand the government stops using fossil fuels.

Protesters screwed chairs to the ground and chained themselves to one another to show support for nations most affected by climate change.

One of its biggest protests was in April 2019, when some of London's busiest routes were brought to a standstill.

That led to more than 1,100 arrests - most on suspicion of not following police instructions to move.

Some activists glued themselves to trains and to the entrance of the London Stock Exchange. Some marched on Heathrow Airport and others chained themselves up.

A year later, in September 2020, the group held 10 days of action called Autumn Rebellion across London, Manchester and Cardiff.

Extinction Rebellion has also take action around the world.

It is not difficult to find people who object to Extinction Rebellion's tactics - from delayed drivers on Twitter to newspaper columnists.

Its supporters have been criticised as "environmental fanatics" who plan to ruin thousands of holidays and risk alienating thousands of potential supporters.

Ahead of the latest protests the Metropolitan Police acknowledged the activists' "important cause". But Commissioner Cressida Dick has previously said the 2019 protests cost the police an extra £7.5m.

Extinction Rebellion says anyone angered by its protests should "find out more about the severity of the ecological and climate crisis".

It has also defended causing criminal damage, such as smashing windows. It says such tactics are sometimes necessary and that it is "super careful" not to put anyone at risk.

Younger people are most likely to agree with its aims, a survey of over 3,000 people carried out after the London 2019 protests suggests.

Among 18 to 24-year-olds, 41% either "strongly supported" or "somewhat supported" the disruption of traffic and public transport in London to highlight Extinction Rebellion's aims.

That compared with 33% of those aged 50-65 and just 26% of over-65s.

It has also received support from public figures, such as the actress Emma Thompson, politicians Diane Abbott and Caroline Lucas and the bands Radiohead and Massive Attack.