Croatia's incumbent President Zoran Milanovic has been returned for a second five-year term of office after comprehensively beating his conservative rival Dragan Primorac at the polls.

With 99 percent of votes counted, Milanovic, who has previously served as prime minister and president of the center-left Social Democratic Party, or SDP, had won more than 74 percent of the vote, compared to just 26 percent for Primorac, from the governing Croatian Democratic Union party, or HDZ.

Although the role of the president is largely ceremonial, the mass rejection of the ruling party has dealt a heavy blow to the authority of Prime Minister Andrej Plenkovic, whose party has dominated Croatian politics since the country achieved independence in 1991.

In his victory speech, Milanovic said the result was a declaration of trust in him by the electorate, but was also sending a message to the government "about the state of affairs in the country … I am asking them to hear it. That is what the citizens wanted to say. This is not just support for me."

The second round of voting was only necessary because Milanovic fell just short of securing 50 percent of the vote out of a field of eight candidates in the first round, at the end of December, necessitating a second vote involving just the top two candidates.

In his concession speech, Primorac said: "Zoran Milanovic and I share completely different spiritual, moral, professional values and thoughts about the future of our homeland".

"The decision was made by citizens, democratically, and as such it must be respected," he added.

However, neither Plenkovic, the prime minister and head of the HDZ, nor Primorac congratulated Milanovic for Milanovic's reelection, a move criticized by former prime minister Jadranka Kosor and many others in Croatia.

Croatia, which has a population of 3.8 million, is the most recent member state of the European Union, having joined in 2013, and adopted the euro as its currency in Jan 2023.

Milanovic, born in 1966, was elected president for the first time during the presidential runoff held five years ago. Prior to that, he served as a Croatian diplomat to the European Union and NATO, and he was Croatian prime minister from December 2011 to January 2016.

Some Western media labeled Milanovic as a NATO critic because he has opposed sending officers to participate in NATO training for Ukrainian soldiers. He has also said that the United States and NATO were engaged in a proxy war against Russia through Ukraine, and slammed Western sanctions on Russia as absurd and useless.

A Croatian president serves a five-year term and can seek reelection once.

Xinhua contributed to this story.