Athens (AFP) - The Greek MEP central to an EU parliament graft scandal awaited a key ruling Wednesday that may keep her behind bars, as she argued innocence in a case allegedly tied to World Cup host Qatar.

A Belgian court is set to decide whether Eva Kaili, who was removed from her vice president post on Tuesday, and three co-accused will remain in custody pending trial in the corruption case.

Kaili’s arrest came during a series of police raids across homes and offices in and near Brussels in which at least 1.5 million euros ($1.6 million) in cash was seized.

The government of Qatar has denied any connection to any wrongdoing in the case.

A Belgian judicial source told AFP that investigators believe that figures representing the Gulf nation’s monarchy had been paying off European politicians to burnish the country’s image.

Qatar is a key energy supplier to Europe, and plays an important intermediary role in several diplomatic tangles.

But it has also been criticised for the alleged mistreatment of migrant workers, most notoriously those who built the World Cup stadiums.

As Kaili sat in a Brussels jail cell, her colleagues in the Strasbourg parliament scrambled to distance themselves from the scandal.

The 44-year-old former television news presenter is the only serving MEP to have been charged. But several more have had their offices put under police seal while investigations continue.

She was arrested last week during a series of raids by Belgian graft investigators on the homes and offices of several MEPs and their assistants or associates.

- ‘False rumours’ -

A Belgian judicial source, confirming reports in Belgian newspapers Le Soir and Knack, said 600,000 euros were found at the home of Italian former MEP Pier Antonio Panzeri, 150,000 euros in Kaili’s flat, and 750,000 in her father’s hotel room.

Kaili’s lawyer Michalis Dimitrakopoulos told AFP that she “did not know of the existence” of the cash found at her home.

Her lawyer said she was “innocent”, and he denied what he said were “false rumours” that she had received bribes from Qatar.

He said her partner, Francesco Giorgi, could have “answers about the existence of this cash”.

Qatar denies any involvement in European corruption.

“Any claims of misconduct by the state of Qatar are gravely misinformed,” an official has told AFP.

Brussels has been rocked by the claims, and European Parliament President Roberta Metsola, defending the integrity of the EU legislature, has sought to portray the alleged bribes as an assault on democracy.

Kaili was one of six people detained. Four have been charged with “criminal organisation, corruption and money laundering” and two released.

One of those released was Luca Visentini, the general secretary of the International Trade Union Confederation, a global labour body that has pushed Qatar on labour rights.