Attorney General William Barr skipped a House hearing Thursday on special counsel Robert Mueller’s Trump-Russia report, escalating an already acrimonious battle between Democrats and President Donald Trump’s Justice Department.

Barr’s decision, made after a disagreement with a House committee over questioning, came the day the department also missed a committee deadline to provide it with a full, unredacted version of Mueller’s report and its underlying evidence. In all, it’s likely to prompt a vote on holding Barr in contempt and possibly the issuance of subpoenas, bringing House Democrats and the Trump administration closer to a prolonged battle in court.