Zagreb, April 17 (IANS/DPA) Croatia is set to hold parliamentary elections on Wednesday in a contest overshadowed by a bitter rivalry between President Zoran Milanovic, a Social Democrat friendly towards Moscow, and conservative Prime Minister Andrej Plenkovic.

The latest polls put Plenkovic's conservative Croatian Democratic Union (HDZ) ahead of the opposition Social Democratic Party of Croatia (SDP).

Milanovic made a surprise announcement a month before the elections that he would seek the post of Prime Minister as the head of the SDP. As President, he has made right-wing populist and pro-Kremlin remarks.

Croatian voters were set to go to the polls in the autumn.

However, observers believe that Plenkovic, who only had a narrow majority in Parliament before it was dissolved in March, wanted the snap election to forestall the threat of a further drop in popularity.

He has been heavily criticised recently for his media and judicial policies, with only a narrow majority of lawmakers backing him.

Polling stations open at 7 a.m. for the nation's 3.7 million eligible voters and are set to close at 7 p.m.

Initial results are expected later on Wednesday evening.