Mueller would appear only under a subpoena, which has been described as a "friendly" subpoena, one that in essence had been planned, Fox News reported.
"Americans have demanded to hear directly from the Special Counsel so they can understand what he and his team examined, uncovered, and determined about Russia’s attack on our democracy, the Trump campaign’s acceptance and use of that help, and President Trump and his associates' obstruction of the investigation into that attack," Nadler and Schiff said in a joint statement.
Mueller had earlier said that he did not wish to appear before lawmakers, noting that “the report is my testimony.”
Mueller released his report earlier in April of this year. In his report, he says he found no basis for accusing President Trump of collusion with Russia during his 2016 campaign. However, extensive redactions in the publicly released version of the report give Trump's opponents hope that the document may contain something that they can use to support their allegations of a wrongful victory in the presidential race. Both Russia and the White House have repeatedly denied all allegations of collusion.