FILE PHOTO - Tomislav Karamarko, president of Croatian Democratic Union (HDZ) party, listens to the national anthem during an election rally at Arena in Zagreb, Croatia, November 5, 2015. REUTERS/Antonio Bronic/File Photo(reuters_tickers)
ZAGREB (Reuters) - The Head of Croatia's conservative HDZ party, the biggest in a collapsed centre-right coalition, resigned on Tuesday after failing to form a new cabinet.
"I promised the party that I will be able to form a new parliamentary majority, which I failed to achieve," Tomislav Karamarko said.
The HDZ last week brought down technocrat Prime Minister Tihomir Oreskovic after falling out with him and a junior coalition partner over a conflict of interest case involving Karamarko.
Croatia is set to hold a snap election, probably in the first half of September, with the date to be set by Croatian President Kolinda Grabar-Kitarovic.
A recent opinion poll shows the HDZ trailing the main opposition party, the Social Democrats, for the first time since the previous election last November.
A Croatian member of the European Parliament, Andrej Plenkovic, has already announced his readiness to compete for the top post in the HDZ.
(Reporting by Igor Ilic; editing by Giles Elgood)