Abdelhadi Sewif is a prominent preacher of Egyptian origin at the Saudi-funded Brussels’ Grand Mosque.
He is alleged to be a Salafist preaching extreme Islamic views at Belgium’s biggest mosque.
Theo Francken, Belgium’s Asylum and Migration State Secretary, said his residence permit has been withdrawn before deportation procedures are implented.
He told radio station BelRTL: “There is a problem with the Brussels’ Grand Mosque, everyone knows that. I have taken the decision to withdraw the residence permit of the imam of that mosque.
“We have enough persuasive evidence to think that the imam is a very radicalised, ultra-conservative Salafist. He poses a danger to society and to national security.”
The battle against Salafism is one of the Belgian government’s “top priorities”, he said.
The Salafist movement – an extreme and austere form of Islam which is strongly influenced by Saudi Arabia’s Wahhabi school of Islam – has been linked to radical Islamist groups such as Islamic State (ISIS), and sees more moderate branches of the faith as heretical.
Belgian authorities told Sewif they would not be renewing his residence permit in March, and he was given until May to leave the country.
But the imam, who has lived in Belgium for 13 years, lodged an appeal against that decision and has not yet left Brussels. A judge is to decide on Mr Sewif’s appeal on October 24.
Brussels’ Saudi-funded Grand Mosque has a reputation as a hotbed of extremism, and has been repeatedly accused of promoting ultra-conservative forms of Islam.