Special counsel Robert Mueller, breaking a two-year silence on his investigation into ties between Russia and the Trump campaign, announced his resignation from the Justice Department on Wednesday so that he can “return to private life.”

Mueller’s statement was relatively brief, about eight minutes, and Attorney General William Barr was given a heads-up about what he would say, according to people who were not authorized to provide details on the record and spoke on condition of anonymity.

The statement came amid demands for Mueller to testify on Capitol Hill about his findings and tension with Barr.

Mueller and Barr have been at odds over the attorney general’s handling of the special counsel’s report on Russia’s interference in the 2016 election and the possibility that Republican candidate Donald Trump’s campaign cooperated with the Russians’ efforts to help him win.

Mueller has remained a Justice Department employee since submitting the report in March, though the Justice Department has not said what work he has been doing.

House Democrats want Mueller to testify publicly, though no date or arrangements have been set, and it’s not clear that he will.

Mueller’s report into meddling in the 2016 campaign did not find that the Trump campaign coordinated to sway the presidential election. But, despite Trump’s repeated assertions to the contrary, it did not reach a conclusion on whether Trump had obstructed justice.

Mueller said in his report that he did not think it would be fair to publicly accuse the president of a crime if he was not going to charge him. A Justice Department legal opinion says sitting presidents cannot be indicted, and Mueller made clear in his report that that opinion helped shape the investigation’s outcome and decisions.

Story by The Associated Press with additional information from CGTN.