He added that Belgium must take "decisive and comprehensive measures" to end its complicity in the genocide.
Demonstrators demanded a full military embargo on Israel, including an end to arms trade and cooperation, as well as a national ban on investments, trade, and diplomatic relations that could contribute to the occupation of Palestinian territories.
The rally, organized by international solidarity groups, was supported by over 200 organizations, including trade unions, Jewish and Palestinian groups, youth movements, religious organizations, cultural associations, and charities.
Israel's genocidal war in Gaza marked its 700th day on Friday, with Israel having killed over 64,000 Palestinians. The military campaign has devastated the enclave, which is facing famine.
Last November, the International Criminal Court issued arrest warrants for Israeli Prime Minister Benjamin Netanyahu and his former Defense Minister Yoav Gallant for war crimes and crimes against humanity in Gaza.