Selahattin Demirtaş must be freed, campaigners in Britain said this weekend as they launched a new initiative pressing the country’s parliamentarians to secure the Kurdish politicians release from prison.

The “Free Selahattin Demirtas” campaign is gathering signatures on a petition demanding that Turkey complies with December’s European Court of Human Rights (ECHR) ruling that the former Peoples’ Democratic Party (HDP) co-chair should be released.

It was initiated by the Centre for Kurdish Progress which warned that “the repression of the Kurdish political opposition has intensified since Turkey’s authoritarian turn gathered pace since 2015.”

“Since then, the HDP’s district and provincial mayors have been removed from their positions on spurious allegations and thousands of party officials have been arrested and imprisoned,” it said in a statement.

Mr Demirtaş has been behind bars since a wave of arrests of HDP parliamentarians in November 2016 after a constitutional amendment removed immunity from prosecution from lawmakers.

He faces a total of 142 years in prison on trumped-up terrorism charges. But the ECHR ruled on December 23 that his continued detention was “politically motivated” and that he should be immediately released.

Turkey’s authoritarian President Recep Tayyip Erdogan predictably ignored the judgment, insisting that the charismatic political leader must remain in prison, raising new charges against him as part of the so-called Kobane case.

This sees Mr Demirtas and 107 other high-ranking HDP officials face life imprisonment on a range of charges including 37 counts of homicide relating to those killed by security services in the 2014 protests in defence of Kobane as it was under siege from Isis.

Mr Erdogan was accused of blocking aid and access to help the Kurds as they faced massacre while facilitating the jihadists as they crossed the border into Syria.

Peace in Kurdistan (PIK) welcomed the move and highlighted the recent motion carried in the European Parliament where MEPs voted overwhelmingly to press the Council of Europe, of which Turkey is a member state, to take firm action to enforce the ECHR decision.

In a statement PIK said: “Turkey simply cannot be allowed to get away with riding roughshod over international law and the decisions of democratic institutions. But it is time that MPs in Britain took a stand and spoke out against the crushing of democracy and the jailing of democratically elected parliamentarians.

“Selahattin Demirtaş and the HDP is the will of the Kurdish people. Millions have voted for him and the party in numerous elections, What is happening is a political genocide. We encourage everyone to sign this petition and send a clear message to their MPs - free Selahattin Demirtas.”

The petition can be signed here.