WASHINGTON — A long-simmering fight between Republican lawmakers and the Obama administration sharply escalated on Wednesday, as a Congressional panel recommended that the House of Representatives cite Attorney General Eric H. Holder Jr. for contempt and President Obama asserted executive privilege to shield Justice Department documents from disclosure.

Immediately after the House oversight committee voted along party lines to approve the contempt recommendation, Speaker John A. Boehner, Republican of Ohio, said the full chamber would vote on the request next week unless Mr. Holder turned over more documents related to the botched gun-trafficking investigation known as “Fast and Furious.”

The president’s move to invoke executive privilege was the first time that he had asserted his secrecy powers in response to a Congressional inquiry. It elevated a fight over whether Mr. Holder must turn over additional documents about the gun case into a constitutional struggle over the separation of powers.

Months in the making, the developments on Wednesday moved the dispute to a new level of partisan acrimony in the midst of a presidential election. Democrats said the move was intended to embarrass Mr. Holder and inflict political damage on the administration, noting that Congress has never cited a sitting attorney general for contempt.