Washington, May 3 (IANS): US House Speaker Nancy Pelosi has accused the Attorney General William Barr of lying to Congress.

Her comments came a day after Barr's testimony to a Senate panel about Special Counsel Robert Mueller's report on Russia's alleged meddling in 2016, the BBC reported on Thursday.

Barr faced sharp questioning about his decision to clear President Donald Trump of obstruction of justice.

The top US law official refused to testify to Democratic-led House Judiciary Committee on Thursday.

The stand-off raises the prospect that Barr -- America's top legal official -- could be held in contempt of Congress.

"He lied to Congress. And if anybody else did that it would be considered a crime," Pelosi said on Thursday.

"Nobody is above the law," she added.

Pelosi's accusation stems from Barr saying he was not aware of any complaints Mueller had about the attorney general's four-page summary of his report.

Mueller wrote a letter to Barr saying the summary lacked "context".

"It wasn't about technicalities," Pelosi told reporters. "The attorney general of the US was not telling the truth to the Congress of the US. That's a crime."

But a spokeswoman for the Department of Justice hit back at Pelosi after her comments.

"The baseless attack on the attorney general is reckless, irresponsible and false," spokeswoman Kerri Kupec said.

Republicans also condemned the remarks. Senator Lindsey Graham told reporters it was an "offensive statement" and said Pelosi should apologise.

"I think it says more about her than it does about Bill Barr," he added.