Turkey's ruling party has formally nominated incumbent President Recep Tayyip Erdogan as its candidate to run in the presidential election set for June 24.

Prime Minister Binali Yildirim said lawmakers of the Justice and Development Party, or AKP, agreed to back Erdogan during a meeting on Thursday.

Meanwhile, four opposition parties are expected to announce over the weekend that they will be joining forces against the AKP in parliamentary elections on the same date.

The main opposition Republican People's Party is reported to have agreed to an alliance with the newly founded Good Party and two smaller parties in a bid to weaken AKP's 16-year dominance.

A pro-Kurdish party, whose former leader and several top lawmakers are in jail fighting terror charges, was kept out of the alliance.