Lisa Page, 38, faced a private congressional hearing over whether anti-Trump bias impacted FBI investigations into Russian meddling or Clinton's emails

Former FBI lawyer Lisa Page has been praised for her 'cooperative' performance at a closed door congressional hearing on Friday, as some Republicans say her testimony confirmed their suspicions of bias.

Page and her former lover, Peter Strzok, are facing the hearings after text messages sent between the pair revealed their hard anti-Trump stance.

The pair were working on Special Counsel Robert Mueller's investigation into Russian meddling in the 2016 Presidential election, and an investigation into Democratic nominee Hillary Clinton's emails.

Page - whose affair with Strzok has led Trump to dub them the 'FBI lovers' - struck a deal with the House Judiciary Committee to testify privately after months of attempts to haul her before Congress, including defying a subpoena to testify publicly this week.

Republican Representative Mark Meadows was one of many from his party to praise the 38-year-old for her 'forthcoming' testimony.

'There is significant new information she has provided,' he told CNN, noting she was a 'very credible witness'.

Other Republicans told the Washington Post the new information has strengthened their belief both investigations were tainted by personal political bias.

Florida Rep. Matt Gaetz told the paper Page's answers: 'heightened my concern that the processes at the FBI were contrived to fit the desired outcomes of people who were biased in favor of Hillary Clinton and against Donald Trump'.

Republican Rep Mark Meadows said he found Page to be a 'very credible witness' and said she provided new information

Florida Rep. Matt Gaetz said Page's testimony reaffirmed his belief political opinion got in the way of FBI investigations

In her near-five-hour session, Page also reportedly answered questions Strzok declined to in his public hearing on Thursday.

Strzok's first open hearing descended into shouting matches during the 10-hour session on Thursday, with Republicans struggling to conceal their emotions and Democrats jumping to the agent's defense.

The hearing became so contentious at times one member called it 'a new low in the United States Congress.'

There were several memorable moments, including one in the afternoon when Republican Rep. Louie Gohmert accused Strzok of wearing a 'smirk' on his face throughout the hearing and tried to shame him by bringing up the FBI agent's affair with former colleague Lisa Page.

He also accused Strzok of being a liar.

'He's lying and we know he's lying and he can probably pass the polygraph,' he said of the agent.

Perhaps aware how different her situation was from her former lover's, Page was seen strolling out of her session on Friday with a smile on her face.

Her hearing is expected to continue on Monday.

Page's hearing was very different to her former lover's, with Peter Strzok facing a shambolic, 10-hour public hearing on Thursday