Pro-Kurdish Peoples' Democratic Party's (HDP) co-leader Figen Yuksekdag has lost her seat in the Turkish parliament after her conviction on terrorism charges.

The development on Wednesday came as the party's other co-leader, Selahattin Demirtas, was sentenced to five months in jail on the charge of insulting the Turkish nation and state institutions.

Both co-leaders were arrested in November 2016 on other terrorism-related charges after their parliamentary immunity was lifted last March.

The politicians, who are facing a total of 180 years in jail if found guilty of all charges, remain in custody pending trial.

READ MORE: HDP applies to ECHR over arrests of its leaders

The decision on the revocation of Yesildag's parliamentary membership, which was announced on the parliament's website on Tuesday, came after the Supreme Court of Appeals approved a lower court decision finding her guilty of making "terror propaganda" on November 27, 2013.

Yuksekdag was accused of chanting slogans that incited violence during the funeral of a "terrorism" suspect. She denies all charges.

Ayse Nur Bahcekapali, the parliament's deputy chief, said the HDP co-leader had become ineligible for her parliamentary seat after the court upheld her sentencing, in accordance with Articles 76 and 84 of the country’s Constitution.

The HDP, on the other hand, said in a statement published on Wednesday that the decision to revoke Yuksekdag's parliamentary membership was "unconstitutional".

"The revoking of [Yuksekdag's] position in parliament once again tramples on the constitution, and it is an effort to give the government's political decision the appearance of legality," the party said.

Ahmet Yildirim, HDP's deputy parliamentary group leader, also said the decision was "void".



"The prosecutors, judges of the said sentencing in question are currently in prison. The ruling of a power hiding behind terrorists cannot be the ruling of the judiciary," Yildirim said, according to Turkish national daily Hurriyet.

At the moment, several Turkish judges and prosecutors are being investigated for their alleged links to Fethullah Gulen, a US-based cleric who is accused of being behind last year's coup attempt by the Turkish government.

'Insulting the Turkish nation'

Meanwhile, a court in northeastern Turkey sentenced HDP's other co-leader, Demirtas, to five months in jail on the charge of insulting the Turkish nation and state institutions.

According to the Dogubayazit Second Regional Court's order, Demirtas is facing jail time for "insulting the Turkish nation, the state of Turkish Republic and public organs and institutions", a judicial source, who spoke on condition of anonymity due to restrictions on talking to the media, told Anadolu agency.

He faces trial in more than 100 other cases that include charges of "managing a terrorist organisation", and faces a jail sentence of more than 100 years.

READ MORE: Turkish PM - Opposition HDP funding 'terror'

Turkey's government has long accused the HDP of being the outlawed Kurdistan Workers' Party's (PKK) political wing.

The United States and the European Union designate the PKK, an armed group that has been fighting for Kurdish autonomy since 1984, as a "terrorist organisation".

The HDP denies direct links with the PKK and promotes a negotiated end to the Kurdish conflict, which has claimed hundreds of lives since a peace process, once led by Erdogan and the AK party, collapsed in 2015.

The HDP claims that the continued detention of its co-leaders and MPs is "politically motivated" and aims to "target and punish the opposition working to organise an effective 'No' campaign during the referendum".

President Recep Tayyip Erdogan has approved a constitutional reform bill earlier this month, in a move paving the way for the referendum on an amendments package that seeks to extend his powers.

The referendum is planned to take place on April 16.

The number of HDP politicians in the parliament has been reduced to 58 after Yuksekdag's removal. However, the party continues to be the third-largest in the parliament after the ruling Justice and Development Party with 317 seats and the opposition Republican People's Party with 134.