Alexander de Croo resigned following the defeat of his Flemish Open Liberal Democratic Party in the Belgian elections.
Belgium has begun efforts to form a new coalition government following an unprecedented election in which centre-right parties won most seats across the country.
In local and national elections on Sunday, the conservative New Flemish Union (N-VA) maintained its decade-long hold in Dutch-speaking Flanders, beating the far-right Vlaams-Berange to come in second.
Meanwhile, in the French-speaking Wallonia region, the center-right Reform Movement overcame the Socialist Party’s long-held dominance and became the largest party in Brussels.
On Monday, Prime Minister Alexander de Croo followed customary practice of submitting his resignation to King Philippe after his Liberal Democrat party saw its support plummet.
“Tonight is a very difficult night for us. We have lost this election,” De Croo said, adding that he took full responsibility for the defeat.
Bart de Wever, mayor of Antwerp and current leader of the N-VA, may be the most likely to be nominated as the first candidate for prime minister, as his party has the most seats (24) in the 150-seat parliament.
“We are completely moving away from the traditional Belgian thinking of the last 50 years, where Flanders was on the right and Wallonia was on the left,” Vincent Laborée, a professor at the University of Leuven, told AFP.
“There is the impression that there is a structural shift of voters towards the centre-right.”
In the coming months, Belgian parties will aim to form a coalition government between mainly centre-right parties in the Dutch-speaking north and more left-leaning parties in the French-speaking south.
Belgium has a complex system of regions and nations and a bad record of protracted coalition talks, which lasted 541 days in 2010-2011.
“Logic dictates that we should move faster this time,” Labordely said, suggesting it would still take six months to find a “landing point”.
For the time being, De Croo will remain caretaker prime minister.
