A 66-year-old senator accused of giving a date-rape drug to a female MP as part of a plot to carry out a sexual assault has been suspended from his centrist party and parliamentary group.
Joel Guerriau is suspected of spiking a glass of champagne he gave to 48-year-old MP Sandrine Josso at his Paris home on Tuesday evening.
He was arrested on Thursday after Josso filed a legal complaint.
The senator and banker faces preliminary charges of "administering to a person, without their knowledge, a substance likely to impair their discernment or control over their actions in order to commit rape or sexual assualt", according to the Paris public prosecutor's office.
Guerriau, who denies the allegations, was placed under judicial supervision on Friday, pending the outcome of the investigation.
His centre-right Horizons party, led by former prime minister Edouard Philippe and allied to President Emmanuel Macron's Renaissance party, said on Saturday that it had suspended the senator and initiated disciplinary proceedings as a first step to kicking him out.
Horizons said it "will never tolerate the slightest complacency towards sexual and sexist violence".
His Senate group, The Independents, said it had also suspended Guerriau and warned he could be expelled.
'State of shock'
Sandrine Josso, a member of the centrist MoDem party, told investigators she felt ill after having a drink on Tuesday night at Guerriau's Paris home, prosecutors said.
The two politicians have known each other for about 10 years but are not in an intimate relationship, they added.
Police searched Guerriau's office and home and found ecstasy.
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