A Belgian court agreed Tuesday to release a European parliamentarian charged under the so-called "Qatargate" graft inquiry from pre-trial detention, on condition he wear an electronic tracker.      

The imminent release of Belgian MEP Marc Tarabella will mean former European Parliament vice-president Eva Kaili is the last suspect still held in custody awaiting eventual trial on corruption charges.

Kaili's bail request will be heard on Thursday, when she will discover whether she will be allowed to return home to house arrest after four months in preventative detention.

Prosecution magistrate Antoon Schotsaert, said the Brussels advisory chamber - the court that decides on the terms of detention - had agreed to release Tarabella, who was detained on February 11. 

Tarabella's legal team confirmed they had learned he would soon be free, under electronic surveillance, and stressed he remains available to investigators and continues to deny all charges.  

Tarabella and Kaili are accused of having used their influence in the European Parliament to push the interests of Qatar, in exchange for cash payments from a Brussels political network.

The government of the Gulf emirate has denied any wrongdoing.

The alleged leader of the graft network, Italian former MEP Pier Antonio Panzeri has confessed to organising the payments, allegedly from agents of Qatar and Morocco, and is now cooperating with the prosecution.  

Another suspect, Italian MEP Andrea Cozzolino, is being held under house arrest in Italy and is fighting his extradition ot Belgium. An appeal hearing is due in Naples on May 2.  

Kaili's partner Francesco Giorgi, a parliamentary assistant close to Panzeri, was released with an electronic bracelet at the end of February.

He and Kaili were among the first arrests in the probe on December 9 last year, when Belgian investigators seized 1.5 million euros in cash during a series of raids on residences in the Brussels area.