Croatia’s incumbent President Zoran Milanovic has swept most votes in the first round of a presidential election, but will have to face a runoff against a ruling party candidate to secure another five-year term.

Incumbent president Zoran Milanovic won the most votes in the first round of Croatia's presidential election on Sunday but fell just short of a majority and will have to go to a second round, results from the State Electoral Commission (DIP) showed.