CNN  — 

Donald Trump Jr. told House investigators that he did not communicate directly with his father when confronted with news reports about his June 2016 Trump Tower meeting, according to multiple sources with knowledge of his testimony.

Instead, Trump Jr. said he was speaking to White House aide Hope Hicks about how to respond to the reports. He said President Donald Trump, according to the sources, was debating between a longer and a shorter statement while the President and Hicks were aboard Air Force One.

Hicks was aboard Air Force One and was speaking with Trump while the statement was being crafted.

Separately, sources said, Trump Jr. said he could not recall some key details about the White House response.

Trump Jr.’s highly anticipated testimony comes as he has faced growing questions on Capitol Hill about the June 2016 meeting at Trump Tower where he met with Russian operatives after being promised dirt on Democratic presidential candidate Hillary Clinton.

Both the House and Senate Intelligence Committees have interviewed several of the participants in the meeting, including when the House panel last week questioned the Russian translator, Anatoli Samochornov, who also attended the Trump Tower session, sources said.

Trump Jr. firmly denied that he had communicated with his father about the June 2016 Trump Tower meeting, according to the sources.

White House lawyer Ty Cobb told CNN on Wednesday that “the fact that each is fully cooperating is consistent with the way the White House has proceeded throughout the series of inquiries.”

The Trump Tower meeting between Trump Jr., Trump’s son-in-law, Jared Kushner, and former Trump campaign chairman Paul Manafort with a Russian lawyer who Trump Jr. believed had dirt on Clinton has been of intense interest to the congressional Russia investigators as well as special counsel Robert Mueller.

While aboard Air Force One, Trump took part in crafting his son’s initial response to the reports of the meeting, which was sent out through the Trump Organization under Trump Jr.’s name.

Mueller has interviewed key White House staff, and he’s likely interested in the discussions surrounding Trump Jr.’s statement – at the very least, they could shed light on how much Trump and others knew about the meetings before learning about them in the press reports. The White House says it didn’t learn about the meeting until it was reported.

CNN’s Gloria Borger contributed to this report.