‘OK fine, it’s a lie’: Ex-Trump aide squirms when CNN host presses him on president’s dishonesty
Former Trump campaign aide Sam Nunberg (Screen cap).

Former Trump campaign aide Sam Nunberg appeared on CNN Monday morning to defend his one-time boss -- and CNN's John Berman made him squirm in his efforts to avoid calling President Donald Trump a liar.

In particular, Berman cornered Nunberg about Trump's declaration that former campaign chairman Paul Manafort only played a minor role in his campaign.

"When the president says he only played a small role for a short time..." Berman began.

"It's wrong," Nunberg interjected.

"Is it dishonest?" Berman asked.

"I'm not going to go into that," Nunberg replied.

Berman, however, would not let it go there.

"It is a lie," he told Nunberg.

"You say it is a lie," Nunberg replied. "I will say inaccurate."

"But why not say that it's a lie?" Berman asked. "President Trump was there. He knows Paul Manafort was his campaign chair... it's a lie."

"Okay, fine," Nunberg finally admitted. "It's a lie."

Later in the interview, Nunberg erroneously claimed that it was unprecedented for a sitting president to be investigated for obstructing justice -- and Berman called him out for being flatly wrong.

"Richard Nixon, Bill Clinton," he shot back. "They were both impeached for obstruction of justice."

Watch the video below.