"We will continue to negotiate for access to the full report. And yes, we will have no choice but to move quickly to hold the attorney general in contempt if he stalls or fails to negotiate in good faith," Nadler said on Wednesday during a committee hearing at which Barr was supposed to testify.
READ MORE: ‘Meaningless to the Broader Public': Barr-Mueller Battle a Strictly DC Obsession
Following Wednesday's testimony before the Senate Judiciary Committee, Barr notified the House panel that he would not attend Thursday's scheduled hearing.
Russia has repeatedly refuted any claims of interference in the US political system, saying the allegations were made up to excuse the election loss of Trump's opponent as well as deflect public attention from actual instances of election fraud and corruption.