Lawmaker M'jid El Guerrab, 34, was accused of "voluntary violence with a weapon" after official Boris Faure was on Wednesday struck twice with a motorbike helmet.
The two men have been in conflict for months, since El Guerrab left the Socialist party for Macron's La République En Marche (Republic on the Move, REM). The president's brand new centrist movement drew members from the traditional right and left-wing of France's political landscape.
Faure has accused El Guerrab of political "opportunism".
A source close to the case said the violence followed Faure allegedly calling El Guerrab, who is his party's deputy for French nationals living in North and West Africa, a "dirty Arab". The men accuse each other of being the aggressor on Wednesday.
"Naturally Mr El Guerrab regrets this turn of events," said his lawyer, Yassine Yakouti, adding that the lawmaker, who claims Faure was physically and verbally aggressive, denies starting the altercation.
El Guerrab has been placed under judicial controls, including a ban on him contacting Faure, who is secretary of the Socialist party's federation of French abroad.
Faure received an emergency operation after the incident and was released from hospital on Saturday, said his lawyer Patrick Klugman.
"Boris Faure's family is absolutely outraged by Mr El Guerrab's statements... We will undertake all legal steps to re-establish Mr Faure as the victim," he added.
Contacted by AFP on Thursday, El Guerrab admitted that he had become violent, saying he regretted "succumbing to the provocation".
The case could cost El Guerrab his REM party membership. On Friday he announced that he was taking time off from his duties.