Corey Lewandowski departs after appearing before the House Intelligence Committee

The Democratic-led US House of Representatives Judiciary Committee said on Thursday it has subpoenaed President Donald Trump's former campaign manager, Corey Lewandowski, to testify in public as part of its investigation of the Trump presidency.

The committee, which is actively considering articles of impeachment against Trump, also served a subpoena on former Trump White House aide Rick Dearborn, a former deputy chief of staff, the committee said in a statement.

Both men figured prominently in former Special Counsel Robert Mueller's 448-page report on his investigation into Russian interference in the 2016 election and could provide lawmakers with fresh insights into an alleged effort by Trump to impede the probe by directing it away from his campaign.

"The committee intends to hold hearings and obtain testimony over the coming months as part of its efforts to hold the president accountable," Judiciary Committee Chairman Jerrold Nadler said in a statement.

"This will help the committee determine whether to recommend articles of impeachment against the president or other... remedies. No one is above the law."

Lewandowski, who is considering a run for the U.S. Senate, and Dearborn were both instructed to appear before the panel on Sept. 17. But it was not clear whether the White House would seek to block their testimony, as it has in the cases of former White House Counsel Don McGahn and other former Trump aides.

Nadler, who has gone to court to compel McGahn to testify about another alleged effort by Trump to curtail the Mueller probe, has said he hopes to decide whether to recommend impeachment by the end of the year.

Lewandowski wrote on Twitter that he was being harassed.

"It's sad and pathetic that Congressman Nadler is harassing private citizens just to fend off his primary challenge from the Left," he wrote. "Mueller's testimony proved what everybody knew all along: No Collusion, No Obstruction. #WitchHunt #OldNews."

Dearborn could not be reached for comment. But his attorney, Bill Coffield, said he would meet with the former White House aide to discuss "his options moving forward."

The committee announced the subpoenas hours before Trump was scheduled to hold a campaign rally in New Hampshire, where local operatives speculated that Lewandowski could announce his Senate candidacy.

Mueller said his investigation did not find sufficient evidence to prove that Trump campaign officials conspired with Russia, despite numerous contacts. He did not determine whether Trump obstructed justice.

However, his report cited Lewandowski and Dearborn as witnesses to one of several episodes of potential presidential misconduct that Democrats believe could support obstruction of justice charges against Trump.

Months after the 2016 election, Trump met with Lewandowski, by then a private citizen, and dictated a message for him to deliver to then-Attorney General Jeff Sessions, according to the Mueller report. The message said Sessions, who had recused himself from the Russia probe, should reverse his recusal and shift the investigation toward future elections.

At a second meeting a month later, Trump asked about the status of the message and said Lewandowski should "tell Sessions he was fired" if he would not meet with the former campaign manager, according to the Mueller report.

Lewandowski then gave Dearborn a typewritten version of the message and asked him to deliver it to Sessions, the Mueller report said. Dearborn told investigators that he did not follow through.

The events followed Trump's alleged efforts to press McGahn to have Mueller removed and then to deny having been instructed to do so, according to the report.