Belgian Prime Minister Charles Michel has vowed to continue his administration as a minority government after the largest party in his coalition quit over his intention to sign the United Nations' controversial migration pact.

The leader of the Flemish-speaking N-VA party, Bart De Wever, announced his party's withdrawal late on Saturday after Michel, a French-speaking liberal, said: "I stand by my word, I will leave for Marrakesh."

World leaders are to meet in the Moroccan city next week to sign the UN migration pact, which has elicited a strong backlash from right-wing parties in many countries.

Conservative governments in Australia, Austria, Hungary, Poland and the Czech Republic have withdrawn their support for the deal, which sets out non-binding measures for regulating global migration.

Michel fended off N-VA pressure last week when a majority in the Belgian parliament voted in favor of maintaining Belgium's support for the agreement.

With N-VA's departure, Michel will need to reshuffle his cabinet to ensure it conforms with a legal statute that requires an equal number of French- and Dutch-speaking ministers.

His French-speaking liberal MR and the Flemish-speaking center-right CD&V and Open VLD parties will remain in the coalition. The next federal election is scheduled for May.