The attorney for an indicted associate of President Donald Trump's personal lawyer says his client is willing to tell Congress that Rep. Devin Nunes, R-Calif., met with Ukraine's former top prosecutor about investigating the activities of Joe Biden and his son, Hunter Biden.

An impeachment inquiry is being conducted over allegations Trump held up aid to Ukraine to encourage its leaders to launch an investigation into Biden and his son, Hunter Biden, who worked as an energy executive in that country.

As vice president, Joe Biden joined a chorus of global pressure for Ukraine to fire then-state prosecutor Victor Shokin.

Trump and Nunes, his chief defender as a ranking member of the House Intelligence Committee that has taken a lead role in the impeachment inquiry, say Joe Biden wanted Shokin out to protect his son when Hunter Biden's employer, Burisma, was under suspicion.

Shokin himself claims he was fired at the behest of the former vice president to ease pressure on Burisma and Hunter Biden.

Joseph A. Bondy, an attorney for Lev Parnas, the indicted associate of Rudy Giuliani, Trump's personal lawyer, confirmed that his client was willing to testify before Congress that Nunes met with Shokin.

"I can confirm that Victor Shokin told Lev Parnas that he had met with Nunes in Vienna in late 2018, and that Derek Harvey informed that they were investigating the activities of Joe and Hunter Biden related to Burisma," Bondy told NBC News.

Derek Harvey is Nunes' investigator.

The story of the offer of testimony was first reported by CNN Friday night. On Wednesday, the Daily Beast reported that Parnas himself helped to arrange meetings in Europe last year for Nunes.

Nunes has been one of the president's most ardent supporters as he faces impeachment proceedings.

NBC News reached out to Nunes and to House Intelligence Committee Chairman Adam Schiff, D-California, but neither responded immediately.

In a statement to Breitbart News on Friday night, Nunes called the CNN and Daily Beast reports "demonstrably false and scandalous."

Parnas was indicted last month for allegedly making illegal campaign contributions. He pleaded not guilty while expressing willingness to cooperate with impeachment investigators.

State Department officials have testified that Giuliani ran his own influence campaign in Ukraine on behalf of the president, and often outside customary diplomatic channels, in an effort to get the country's leaders to launch an investigation into the Bidens.

Read more from NBC News:

Trump talks impeachment with two Senate Republicans who may not be with him

Does Ukraine have the DNC server like Trump says? We fact checked that.

Documents released to ethics group show Giuliani, Pompeo contacts before Ukraine ambassador ousted