The House Intelligence Committee is considering subpoenaing former National Security Adviser John Bolton to testify about his knowledge of President Donald Trump s dealings with Ukraine, committee chairman Adam Schiff (D-Calif.) said Sunday.

Its certainly something that we are considering, Schiff said during an appearance on CBS Face The Nation when asked whether the committee would subpoena Bolton.

Look, Americans want to see a fair trial in the Senate, he continued. They want to see a trial thats fair to the president and they want to see a trial thats fair to the American people, that brings all the facts forward.

House Speaker Nancy Pelosi (D-Calif.), who hasnt yet sent the articles of impeachment against Trump to the Senate, told ABCs This Week earlier Sunday that the lower chamber hasnt ruled out subpoenaing Bolton.

So if the Senate does not subpoena John Bolton and other witnesses, will the House move to subpoena them? asked host George Stephanopoulos.

Its not excluded, but well see what they do, Pelosi said. But we do think that theres enough evidence to remove the president from office. But weve done our job. Weve defended the Constitution of the United States. We would hope that the Senate would do that as well.

House impeachment investigators asked but did not subpoena Bolton to testify during its impeachment inquiry late last year; however, he refused to do so unless a judge ruled on whether witnesses should follow congressional testimony requests or the White Houses orders not to appear.

Bolton, who served as Trumps national security adviser from April 2018 to September 2019, has direct knowledge of the presidents interactions with Ukraine. He was on the infamous July 25 phone call between Trump and Ukrainian President Volodymyr Zelensky, which later became the focus of the whistleblower complaint that prompted the impeachment investigation.

Bolton reportedly objected to Trumps pressure campaign to get Ukraine to investigate former Vice President Joe Biden , a frontrunner in the 2020 Democratic presidential primary race.

Bolton said earlier this month that hes prepared to testify before the Senate should lawmakers call witnesses during a potential impeachment trial. But Senate Majority Leader Mitch McConnell (R-Ky.) has so far indicated that he will not have witnesses at the trial and hopes to end the impeachment process as quickly as possible.

Theres little sense in bringing Bolton into the House and not allowing the senators to see his testimony, Schiff said Sunday. If theyre going to be the triers of fact and they will be they should hear from the witness directly. [Bolton] has offered to come forward and testify. There is no reason not to have him testify unless you just want to cover up the presidents wrongdoing.