Croatian Foreign Minister Davor Ivo Stier resigned on Monday, saying he wanted to devote himself to activities within his conservative HDZ party, following the formation of a new coalition including the conservatives and the liberals.

Last week, the HDZ, led by Prime Minister Andrej Plenkovic, struck a deal with the Croatian People’s Party (HNS), representatives of national minorities and a few smaller parties to stay in power and avert a second snap poll in less than a year.

Local media reported that Stier, who has worked closely with Plenkovic ever since they were both deputies in the European Parliament, was not happy about the deal with the liberals.

“I resigned today to be able to devote myself strongly to the party’s business as political secretary … I assessed that I can contribute more strongly to Christian democratic values as a parliamentary deputy,” Stier told reporters.

Before the current coalition, the HDZ shared power with the center-right Most (“Bridge”) party, a junior partner it fell out with in April over a no-confidence vote in Finance Minister Zdravko Maric.

In an interview with the state television late on Monday, Plenkovic said that Stier would be replaced by the current state secretary in the foreign ministry, Marija Pejcinovic Buric.

“This resignation won’t have immediate negative effects for the new ruling coalition but is certainly a blow to Plenkovic.

It must cause unease, as they were working closely for a certain period,” said political analyst Davor Gjenero.