Belgian Prime Minister Charles Michel has offered his resignation just days after one of his main coalition partners quit in a row over migration.
Mr Michel lost the backing of the nationalist New Flemish Alliance (N-VA) over his support for a UN migration deal signed in Marrakesh last week.
He announced his intention to resign after opposition parties refused to support his minority government.
Mr Michel told King Philippe of his decision late on Tuesday.
The king has yet to announce whether he will accept the resignation.
Belgians were due to go to the polls in May and the king will meet party leaders on Wednesday to decide whether there is any support for early elections.
Mr Michel, 42, took office in October 2014 after forming a right-wing coalition, becoming at 38 the country's youngest prime minister since 1841.
He may stay on as caretaker prime minister until parliament is dissolved in April. He rejected the idea of early elections in a speech to parliament on Tuesday.
Mr Michel had previously defended the Marrakesh migration pact, saying it presented an "opportunity for better European and international co-operation".
Belgium's UN ambassador made it clear that the signing of the accord would go ahead in New York on Wednesday, despite Mr Michel's decision to tender his resignation.
The deal, which is not legally binding, seeks an international approach to migration that "reaffirms the sovereign rights of states to determine their national migration policy" and asserts the "fundamental" importance of legal migration.
But critics in Europe believe it will lead to increased immigration to the continent.
In July, UN members agreed the Global Compact for Safe, Orderly and Regular Migration.
It was signed by 164 countries, with the US and a number of European states - including Austria, Hungary, Italy, Poland and Slovakia - refusing to formally adopt the agreement.
Over the weekend, thousands of demonstrators marched in Brussels against the pact. Police deployed tear gas and water cannon as clashes broke out.
A counter-protest organised by left-wing groups and charities in the city centre drew about 1,000 people.