Last year, British police were granted anti-protest powers following years of disruptive demonstrations by environmental activists.

The United Nations Special Rapporteur on Environmental Defenders Michel Forst said he had received “extremely worrying information” about “an increasingly severe crackdown” during a recent visit to the UK.

“Regressive laws” were being used to give environmental and climate activists severe penalties, “including in relation to the exercise of the right to peaceful protest,” he warned in a statement on Tuesday.

“The right to protest is a basic human right. It is also an essential part of a healthy democracy,” he added.

Forst is an independent expert appointed under the UN’s Aarhus Convention, which provides for justice in environmental matters.

The UK is a signatory of the convention.

Last year, British police were granted anti-protest powers by the government following years of disruptive demonstrations by environmental activists.

But Forst said now peaceful protestors were being persecuted for the criminal offence of “public nuisance”, which is punishable by up to 10 years jail time.

Last month, a peaceful climate protestor who took part in a slow march for about 30 minutes was sentenced to six months in prison.

The expert stressed that before the arrival of these “regressive” laws “it had been almost unheard of since the 1930s for members of the public to be imprisoned for peaceful protest in the UK”.

He added that it was impossible to understand that some judges had barred “environmental defenders from explaining to the jury their motivation” for protesting “or from mentioning climate change at all”.

Forst also slammed the British government’s harsh bail conditions on environmental protestors.

He said, “Environmental defenders may be on bail for up to two years from the date of arrest to their eventual criminal trial.”

He pointed out that severe bail conditions could adversely affect personal lives and mental health.

Forst warned that environmental activists were frequently publicly condemned in British media and by politicians, placing them at heightened risk of threats, abuse and physical attacks.

This “toxic discourse”, he said, “may also be used by the state as justification for adopting increasingly severe and draconian measures against environmental defenders”.