Dassault is attempting to distance itself from a corruption scandal surrounding its bid to win South Korea's F-X fighter competition with the Rafale.
The French manufacturer says it has broken ties with local trading company Comet International, which had been one of its agents in the campaign.
The move follows the arrest by military police of South Korean air force Col Cho Joo-hyong on suspicion of receiving an unauthorised 11 million won ($8,400) payment from Comet.
A second air force officer, who worked with Cho on the F-X evaluation team, has also been arrested.
Cho is known to have made an anonymous appearance on local television earlier this month, during which he claimed senior defence ministry officials put pressure on the team to adjust their interpretation of technical evaluation results to favour Boeing's F-15K instead of the Rafale.
Investigators are meanwhile trying to determine whether Comet was also behind the leak to the South Korean media of documents detailing the technical evaluation results, which awarded the highest marks to the Rafale.
Though Dassault could theoretically be disqualified from the bidding if it were proven to have acted improperly, the investigation is unlikely to be completed until after Seoul selects an F-X winner. The decision is expected next month.
Boeing is tipped to win the order with the F-15K because of the USA's close defence ties with South Korea. Also competing are the Eurofighter Typhoon and Sukhoi Su-35.