Top French officials were to appear for fresh hearings Wednesday over the rogue security aide scandal which has engulfed the government of President Emmanuel Macron, who has broken his silence over the case by saying he bears the sole responsibility for the events.

The disgraced aide, 26-year-old former bodyguard Alexandre Benalla, was dismissed last Friday after videos emerged of him beating a protester while wearing a police helmet and armband during a May Day protest in Paris.

"What happened on May 1 is terrible, serious, and for me it was a disappointment and a betrayal," Macron told a group of lawmakers in his majority Republic on the Move (LREM) party late Monday.

"The only person responsible for this affair is me, and me alone," he said, according to lawmakers present at the gathering.

"The one who knew about and approved the punishment decided by my aides, it's me and nobody else."

Benalla was given a two-week suspension without pay days after the incident and removed from organising the president's security during his trips.

But the alleged assault of the young man was not reported to prosecutors, who opened a probe after French daily Le Monde published the video last week.

Opposition lawmakers have accused the government of a cover-up and have paralysed parliamentary debate while launching investigative committees in both the National Assembly and Senate.

Several cabinet members and security chiefs were to appear before the panels Wednesday, including a Senate hearing for office director Patrick Strzoda.

Strzoda had already told lawmakers Tuesday that he decided there weren't enough elements to justify turning Benalla over to prosecutors, not least because no criminal complaint had been filed against him.

Macron's chief of staff Alexis Kohler will appear before the Senate committee on Thursday.

Opposition lawmakers say Macron still needs to answer questions over what has been dubbed "Benallagate", including reports that the former chief of security during his 2017 campaign enjoyed a series of perks unusual for someone of his rank.

"It's not among his LREM deputies, among his own, that the president should discuss this, but before the French people," Gerard Larcher, the Senate president, told French daily Le Figaro.

"My feeling is that our fellow citizens are a bit stunned by this. The government should be careful," he said.

After the first video emerged of Benalla striking a young man at least twice during scuffles at the picturesque Place de la Contrescarpe in Paris as riot police looked on, another showed him violently wrestling a woman to the ground.

Benalla has been charged with assault and impersonating a police officer, while also illegally receiving police surveillance footage in a bid to claim his actions were justified.

Vincent Crase, an associate and security agent employed by the LREM who was also at the scene, has also been charged, as have three police officers.

It remains unclear how Benalla obtained the police armband.

The head of the police oversight body, Marie-France Moneger-Guyomarc'h, also testified on Tuesday that police had no reason to believe the person in the Benalla video was not an officer and that the violence "was not illegitimate (if) carried out by police officers".

The scandal comes as Macron's ratings slump, with 60 percent reporting an unfavourable opinion in an Ipsos poll published Tuesday -- a record low for the centrist.

An Elabe poll, released before Macron spoke on the issue, found 80 percent were "shocked" by the "Benallagate" affair.

"The problem isn't Alexandre Benalla's misconduct but rather the structure that made it possible," said Bruno Cautres, a political scientist in Paris.

"No matter the administrative or judicial consequences of this affair, it will mark a before and after for Emmanuel Macron."