The European Parliament on Monday announced its chief, Roberta Metsola, had launched "an urgent procedure" to lift the immunity of two MEPs amid a corruption scandal linked to Qatar.
The parliament did not give the lawmakers' names but said it was in response to an investigation by Belgian law enforcement into the graft allegations.
Sources briefed on the Belgian probe told AFP the two MEPs targeted by the procedure were an Italian, Andrea Cozzolino, and a Belgian, Marc Tarabella.
Both are members of the centre-left Social and Democrats grouping in the parliament.
The development follows a string of Belgian police raids in December on the addresses of MEPs, former MEPs and lobbyists that turned up a total 1.5 million euros ($1.6 million) in cash.
There are suspicions that the money was tied to alleged graft in the European Parliament benefiting Qatar.
Qatar denies having a role in any wrongdoing.
The scandal has shaken the European Parliament, with one of Metsola's vice presidents, Greek MEP Eva Kaili, among four suspects arrested in the raids in Belgium.
Through her lawyer, Kaili has denied knowing of the existence of 150,000 euros found in her home and asserted she is innocent.
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