Ukraine-sceptic government ally Peter Pellegrini won Slovakia's presidential election Saturday against pro-Western diplomat Ivan Korcok.

Opposition-backed Korcok conceded defeat as nearly complete results showed he had received 47 percent of the vote against former Prime Minister Pellegrini's 53 percent.

Pellegrini will replace outgoing President Zuzana Caputova, who is staunchly pro-Ukraine like Korcok.

Pellegrini, 48, thanked his coalition partners after his win.

It is a huge satisfaction, Pellegrini said in Bratislava, vowing to ensure that Slovakia remains on the side of peace and not on the side of war.

Ahead of the run-off, Pellegrini had said he advocated peace talks with Russia. Korcok argued he did not believe Ukraine should give up territory to achieve peace.

Divisions over the Ukraine war dominated the run-off vote given the starkly opposing views of the conflict by the two candidates for the post that is largely ceremonial.

Russia's invasion of Ukraine became a fixture of the electoral campaign in the EU and NATO member of 5.4 million (54 lakh) people after populist Prime Minister Robert Fico, Pellegrini's ally, questioned Ukraine's sovereignty and called for peace with Russia.

Though the office is largely ceremonial, Slovakia's president has the power to ratify international treaties as well as veto laws passed by parliament and appoint top judges.

The position also serves as the commander-in-chief of the armed forces.

The newly elected president Peter Pellegrini will be sworn in on June 15.