Congressional investigators want to question Trump's longtime secretary, Rhona Graff, in Russia probe

— -- Congressional investigators want to question President Donald Trump’s longtime personal secretary as part of their ongoing probe into a controversial meeting between Trump campaign officials and a Russian lawyer promising dirt on Hillary Clinton, ABC News has learned.

Rhona Graff, a senior vice president at the Trump Organization who has worked at Trump Tower for nearly 30 years, has acted as a gatekeeper to Trump. She remains a point of contact for the sprawling universe of Trump associates, politicians, reporters and others seeking Trump's time and attention, even now that he's in the White House.

Graff's position in Trump's orbit recently gained attention after Donald Trump Jr. released a June 2016 email exchange with British publicist Rob Goldstone leading up to the meeting with Russian attorney Natalia Veselnitskaya at Trump Tower.

“I can also send this info to your father via Rhona," Goldstone wrote Donald Jr. in the email, "but it is ultra sensitive so wanted to send to you first.”

Graff was not on the email chain and it's unclear if Goldstone ever made direct contact with her.

“Since her name is in the email, people will want her to answer questions,” said Rep. Peter King, R-New York, a member of the House Intelligence Committee who knows Graff. “If you go into Trump Tower, you’re going to mention her name.”

The president, who has said he does not use email, communicated with associates for years through Graff. "Everybody knows in order to get through to him they have to go through me, so they are always on their best behavior,” Graff told Real Estate Weekly in 2004.

According to sources familiar with Trump's habits, Graff would often receive emails on his behalf and print them out for his review. If Trump felt the need to respond he would write on the print out -- typically with a Sharpie pen -- and hand it back to Graff so should could scan the message and send it on electronically.

Asked if he would seek an interview with Graff or examine her records, the top Senate Republican leading the Russia probe did not rule it out. “The Committee has cast and will continue to cast a wide net,” Sen. Richard Burr, R-N.C., told ABC News.

Attorney Alan Futerfas, who serves as outside counsel representing the Trump Organization and its employees, says Graff has not yet been contacted by congressional investigators.

"We have yet to receive such an inquiry but will, of course, continue to cooperate with any Committee seeking information,” Futerfas told ABC News when asked about the possibility of Graff being questioned or asked for records by investigators looking into the Russia matter.

Graff has not been accused of wrongdoing.

Senate and House Intelligence Committee aides declined to comment on the record about whether Graff has been contacted or would be soon.

"We’re going to want to hear from everyone connected to this," Rep. Adam Schiff, D-California, the committee's top Democrat, said on July 11. "We’re also going to want to see, as referenced in that email, whether the president’s assistant received any communications from the Russians as well. That was another channel alluded to in those emails."

The Trump Tower meeting continues to be a focus in the three congressional investigations into Russian election interference.

“I think we should hear from every individual who is mentioned in the Don Jr. email chain to understand what was happening,” said Rep. Eric Swalwell, D-California, a member of the House Intelligence Committee.

Jared Kushner, a White House senior adviser and Trump son-in-law who attended part of the meeting with Veselnitskaya, was interviewed by the House and Senate Intelligence Committees last month.

Senate Judiciary Committee investigators, also probing the meeting, are reviewing 20,000 pages of documents handed over to the committee by the Trump Campaign earlier this week, according to a committee aide.

The panel also received more than 400 pages of documents from Paul Manafort and 250 pages of documents from Donald Trump Jr.

The Judiciary Committee, along with the House and Senate Intelligence Committees, all want to interview Manafort and Trump Jr. in public and private this fall -- along with anyone associated with the meeting.

ABC's John Santucci, Justin Fishel and Jonathan Karl contributed to this report.