(CNN) An associate of Rudy Giulian i -- Lev Parnas -- has initiated talks with impeachment investigators through his attorney.

The attorney, Joseph Bondy, told the team from CNN's "Anderson Cooper 360" that he had sent a letter to congressional investigators saying Parnas will comply with a congressional subpoena for his documents and testimony.

However, Bondy said he would not use the word "cooperate."

Bondy also accused President Donald Trump of falsely denying he had a relationship with Parnas.

Parnas and three other Giuliani associates were indicted on charges of allegedly funneling foreign money into US elections. All have pleaded not guilty.

Bondy told The Washington Post on Monday that Parnas plans to "honor and not avoid" requests from Congress "to the extent they are legally proper while scrupulously protecting Mr. Parnas' privileges including that of the Fifth Amendment" in avoiding self-incrimination.

Trump has repeatedly denied knowing Parnas or his associate Igor Fruman, who was also arrested while trying to leave the country last month. In photos posted to a now-inactive Facebook page, Parnas and Fruman frequently sought to tout a close relationship to the President, his family and his advisers -- including Giuliani.

"I don't know those gentlemen. Now it's possible I have a picture with them because I have a picture with everybody, I have a picture with everybody here," Trump said last month, adding that someone told him there "may be" a photo with them "at a fundraiser or somewhere, but I have pictures with everybody."

He continued, "I don't know them. I don't know about them. I don't know what they do but I don't know, maybe they were clients of Rudy. You'd have to ask Rudy, I just don't know."

News footage reviewed by CNN's KFile from an October 20, 2018, election rally in Nevada shows Parnas standing behind Trump.

Bondy told The Post, "Any sentient being looking at the public record of the President and Parnas together — during intimate dinners, waving to each other at rallies, taking pictures together, and of Parnas's alleged involvement with the President's lawyer Rudy Giuliani — could divine that the President and Parnas knew each other."

The House impeachment inquiry is rooted in a whistleblower complaint that deals with a phone call Trump had with Zelensky on July 25. A transcript of the conversation released by the White House shows Trump repeatedly pushed Ukrainian President Volodymyr Zelensky to investigate former Vice President Joe Biden and his son, Hunter.

There is no evidence of wrongdoing by either Joe or Hunter Biden.

US officials were concerned, the whistleblower said, about Giuliani and his contacts with Ukrainian officials. The whistleblower alleges that US officials believed Giuliani was a conduit for messages between the President and officials in Kiev and that he was at the helm of a problematic "circumvention of national security decision-making processes."