The next parliamentary elections in Croatia will be held on Dec. 8 with the leftist government facing a strong challenge from the conservatives amid the migrant crisis and bad economy.

President Kolinda Grabar Kitarovic on Monday formally called the vote — Croatia's first parliamentary election since it joined the European Union in 2013.

The balloting will be held amid economic problems and regional tensions fueled by the influx of tens of thousands of migrants passing through the Balkans — including Croatia — toward Western Europe.

Prime Minister Zoran Milanovic's government led the country when Croatia became the EU's 28th member state, but many among Croatia's 4.2 million people have been disappointed with the slow recovery and widespread joblessness.

Opposition candidate Grabar Kitarovic won the presidency in an election last December.