The imprisoned Kurdish leader Selahattin Demirtas announced Thursday that he was retiring from active politics, and called on his party officials to do “thorough self-criticism” after a below-expected performance in Turkish elections last month.

The pro-Kurdish Peoples’ Democracy Party (HDP), which contested the election under another party’s banner due to the risk of being banned due to alleged links with militants, secured 8.79% of the vote in the May 14 parliamentary election. In the 2018 elections, the HDP won 11.7% of the vote. However, it remains the third party in the Turkish National Assembly after the May elections.

“I sincerely apologize from our people that we have not been able to carry out a politics worthy of them,” former HDP leader Selahattin Demirtas told the Artigercek news website from the Edirne prison where he is being held in northwestern Turkey. “Although I will continue my struggle with resistance from prison like all my comrades, I withdraw from active politics at this stage”.

A prosecutor filed a request to ban the HDP in March 2021, accusing it of having ties to the outlawed Kurdistan Workers’ Party (PKK), which is designated a terrorist organization by the United States, the European Union, and Turkey.

The HDP denies having links to the PKK, which has been fighting the Turkish state for decades in a conflict for autonomy that has left at least 40,000 people dead.

Demirtaş was co-chairman of the HDP from 2014 to 2018. Despite being in prison since 2016, he has remained an important political figure on the Turkish political scene, issuing daily political messages through his Twitter account to his more than two million followers.

The HDP and its allies did not nominate a candidate in the presidential election and supported the main opposition candidate, Kemal Kilicdaroglu. In the runoff on May 28, President Recep Tayyip Erdogan won 52.2% of the vote, extending his 20-year stay in power. Kilicdaroglu got 47.8%.

Demirtas said he would remain a member of the HDP and called on his party to do self-criticism. “What we need most it is internal party democracy. When intra-party democracy declines, mistakes follow one another.”

Demirtas had run for president twice, first in 2014 and again behind bars in 2018, when he came third with 8.4% of the vote.

He said he had told the HDP leadership before the election that he was willing to run again in this presidential election, but his offer was rejected.

“My candidacy could have increased our votes… But I still don’t know why it was rejected,” he said.

Demirtas, 49, was previously sentenced to three years in prison for promoting the president. He remains in prison and faces a life sentence in a trial with more than 100 other HDP politicians accused of inciting the 2014 protests in which dozens of people died.

In his victory speech, Erdogan said Demirtas’ release was unlikely and called him a “terrorist”.

Kilicdaroglu had pledged that if he won the election, Turkey would comply with rulings by the European Court of Human Rights calling for Demirtas’ release.