Manhattan federal prosecutors are seeking to learn whether Rudy Giuliani could have profited from a natural gas business plan pitched by his two now-indicted buddies, the Wall Street Journal reports.

Lev Parnas and Igor Fruman had pitched a business plan involving their company Global Energy Producers, in which Ukraine would import U.S. LNG via a pipeline the the firm was to build across Poland.

The extent of Giuliani’s involvement in the firm is unclear. He denied any link to the company in an interview with the newspaper.

But Kenneth McCallion, an attorney for former Ukrainian Prime Minister Yulia Tymoshenko, said that the pipeline proposal was “part of the essential package” of what Parnas and Fruman were pitching.

A Manhattan federal grand jury indicted the pair last month on charges relating to a criminal campaign finance scheme. The allegations partly relate to a $325,000 contribution the pair made to a pro-Trump Super PAC that was incorrectly listed as flowing from Global Energy Producers.

The pair reportedly also asked Ukrainian officials whether they could pay back a multi-million dollar debt supposedly owed to Dmytro Firtash, a billionaire gas oligarch who hired Parnas.