Pro-PKK Peoples' Democratic Party (HDP) Deputy Sırrı Süreyya Önder called on the main opposition Republican People's Party (CHP) to form a joint bloc in the presidential election in 2019.

Speaking to Dihaber news, Önder said that the new bloc should have an "opinion consensus" and aim to form the government in the 2019 elections.

"Forming a bloc with the HDP, the CHP and many other partners is a must. If it is achieved, it shouldn't be a ‘alliance of slogans' rather an ‘alliance of action and joint program,'" he said.

Previously, the HDP lent support to CHP Chairman Kemal Kılıçdaroğlu's 400-kilometer march from the capital, Ankara, to Istanbul on July 9, in the name of justice. Some HDP lawmakers marched alongside the CHP leader.

The government has long criticized the HDP for failing to distance itself from the PKK. Yüksekdağ drew heavy criticism for her alleged pro-PKK stance with her remarks in 2015.

"We support the YPJ [Women's Protection Units], the YPG [People's Protection Units] and the PYD [Democratic Union Party], and we do not see any harm in mentioning and defending them," she had said in July 2015.

Yüksekdağ also praised the PKK and described it as "a national liberation movement and also an organization that stands for democracy and equality."

Several HDP deputies, including party leaders Yüksekdağ and Demirtaş, were arrested last November on terrorism charges. The lawmakers began facing prosecution under anti-terrorism legislation after their parliamentary immunity was lifted in March 2016.