United States Commerce Secretary Wilbur Ross confirmed on Tuesday he will divest his stake in shipping firm Navigator Holdings, as a group of Democratic senators formally requested an investigation into Ross’ financial holdings and potential conflicts of interest.

Commerce Department spokesman James Rockas confirmed the plan to divest in response to questions from the International Consortium of Investigative Journalists. The news comes the week after ICIJ, the New York Times and other media partners reported that Navigator had earned more than $68 million since 2014 from Sibur, a gas and petrochemicals companies whose owners include Vladimir Putin’s son-in-law, and that Ross had kept a stake in the shipping company while serving as Commerce Secretary.

The revelations were part of the Paradise Papers, a global investigation based on a leak of more than 13.4 million offshore documents that was obtained by the German newspaper Süddeutsche Zeitung and shared with ICIJ.

The day after story was published, Ross told Bloomberg Television that he had done nothing wrong but would “probably not” keep his stake in Navigator. He said his inclination to sell his interest in Navigator was not connected to the news reports and stopped short of committing to divest.

Yesterday, the Commerce Department said Ross would sell his remaining shares.

“He has divested most of his interest in Navigator Holdings and will be completely divested in the near future,” Rockas told ICIJ.

Ross’ complex financial holdings and convoluted ethics disclosures have prompted six Democratic senators to call for an investigation by the Commerce Department’s Inspector General into whether Ross has complied with the divestment and recusal requirements in the ethics agreement he signed before taking office.

“Secretary Ross is supposed to recuse himself from actions that would affect the assets he has been allowed to retain,” wrote the senators Richard Blumenthal (D-CT), Maggie Hassan (D-NH), Cory Booker (D-NJ), Maria Cantwell (D-WA), Tammy Baldwin (D-WI), and Tammy Duckworth (D-IL) in a joint letter to Commerce Department Inspector General Peggy Gustafson. “Whether he has done so is questionable.”

Divesting his stake in Navigator, when completed, would remove one of the most significant potential conflicts of interest facing Ross – although questions from the senators remain about  whether he fully lived up to his ethics agreement before the divestiture and whether he still holds any other assets that could conflict with his duties as Commerce Secretary.