A group of opposition Republican People's Party lawmakers have called for their party leader to step down following a poor showing in Sunday's presidential election.

The party, known by the Turkish acronym CHP, fielded a joint candidate with other opposition parties in the election, which the ruling Justice and Development Party's Recep Tayyip Erdogan won with 51.79 percent of the vote.

In a press conference in Ankara on Tuesday, the capital's CHP lawmaker Emine Ulker Tarhan called on party chairman Kemal Kilicdaroglu to resign and convene an extraordinary party congress.

Flanked by fellow lawmakers Dilek Akagun Yılmaz, Suheyl Batum, Birgul Ayman Guler, Nur Serter and Isa Gok, Tarhan claimed the party leadership had been warned about the danger of selecting a joint candidate who represented both the center-left CHP and right-wing Nationalist Movement Party.

She said: "We anticipated the coming events [the loss of the election] and we gave a warning but we were confronted by threats."

Tarhan had been suggested as a potential presidential candidate before academic Ekmeleddin Ihsanoglu was selected. He received 38.44 percent of the vote, coming second in the three-man race in front of Selahattin Demirtas, candidate of the pro-Kurdish Peoples' Democratic Party.

She called on the party congress to protect the future of the CHP and Turkey.