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.

But Republicans accused the administration of a “cover-up” and questioned the validity of Mr. Obama’s claim of executive privilege for internal Justice Department deliberations.

“Our purpose has never been to hold the attorney general in contempt,” said the committee’s chairman, Representative Darrell Issa, Republican of California. “Our purpose has always been to get the information the committee needs to complete its work — that it is not only entitled to, but obligated to do.”

In a statement, Mr. Holder portrayed the committee’s action as “political theater,” saying Mr. Issa was trying to “provoke an avoidable conflict between Congress and the executive branch” as an “election-year tactic.”

The Republican takeover of the House after 2010 gave Mr. Issa a platform to investigate the Obama administration, which he has called the “most corrupt” in history. A critic of Mr. Holder from the start of his chairmanship, Mr. Issa focused on Fast and Furious, a gun trafficking inquiry by the Phoenix division of the Bureau of Alcohol, Tobacco, Firearms and Explosives.

From late 2009 to early 2011, A.T.F. agents allowed guns to “walk” — choosing not to interdict them swiftly in an effort to build a bigger case. But they lost track of about 2,000 guns, most of which probably reached a Mexican drug network. Two of the weapons were found near a December 2010 shootout at which a Border Patrol agent, Brian Terry, was killed. It has since come to light that the bureau had used similar tactics three times in the Bush administration, although they lost track of fewer weapons.

Mr. Holder, a recurring lightning rod for conservative anger, has repeatedly tangled with House Republicans and been associated with some of the administration’s most liberal policies, including refusing to defend a law barring federal recognition of same-sex marriages, challenging an Arizona law cracking down on illegal immigrants and invoking civil rights laws to block Republican-led efforts to impose voter photo ID laws.

Mr. Issa’s inquiry has drawn extensive attention from conservative news outlets, including Fox News, and set off a drumbeat of enthusiasm among conservative bloggers and on social media over the prospect of bringing down Mr. Holder over it. “It’s clear that not backing down is important to both sides,” said Bruce Buchanan, a political science professor at the University of Texas at Austin.

Mr. Issa was initially seeking a broad range of documents, including some that were sealed by court order. But the contempt citation is more narrowly focused on internal Justice Department deliberations last year amid the Congressional investigation.

The administration has already released a similar set of documents from before Feb. 4, 2011, showing how it drafted an early letter that falsely told Congress that A.T.F. always made every effort to interdict guns, which the department later retracted. Those documents showed that employees in Arizona had insisted to the officials who drafted the letter that no guns had walked in Fast and Furious.

The administration said it was making an exception for release of the pre-Feb. 4 documents to show that it had not deliberately misled Congress, but that it would not turn over records of internal deliberations after that. Republicans, however, insist they have a right to see those too.

On Tuesday evening, Mr. Holder offered to give the committee some of the disputed documents if Mr. Issa would agree to end the fight over contempt, but the lawmaker refused to consider doing so until he saw them.

On Wednesday morning, Deputy Attorney General James Cole said in a letter to Mr. Issa that the president was claiming privilege over the documents because their disclosure would chill the candor of future internal deliberations. However, he suggested that there might still be a way to negotiate the release of some of the contested documents.

The invocation of executive privilege by Mr. Obama added a new element to the drama. While there is little dispute that the privilege covers communications made directly to the president and among his White House advisers, it is far less clear that the privilege trumps Congress’s right to subpoena internal communications within an agency.

There is little Supreme Court precedent to clarify how expansive the privilege is, in part because such disputes are usually resolved with a compromise, said Mark J. Rozell, a George Mason University political science professor and author of “Executive Privilege: Presidential Power, Secrecy and Accountability.”

A White House spokesman cited several examples of Republican presidents asserting executive privilege to withhold agency documents not involving presidential communications.

Still, Mr. Obama appeared to adopt a narrower view of executive privilege during the 2008 campaign. Then a senator, Mr. Obama was asked by The Boston Globe whether he believed that executive privilege covered documents about decision-making within the executive branch not involving confidential advice communicated to the president.

He replied: “With respect to the ‘core’ of executive privilege, the Supreme Court has not resolved this question, and reasonable people have debated it. My view is that executive privilege generally depends on the involvement of the president and the White House.”

House Republicans adopted a more limited view of executive privilege as requiring White House involvement, suggesting it was a victory for their side either way.

“The White House decision to invoke executive privilege implies that White House officials were either involved in the Fast and Furious operation or the cover-up that followed,” said Michael Steel, the spokesman for Mr. Boehner. “The administration has always insisted that wasn’t the case. Were they lying, or are they now bending the law to hide the truth?”

But Representative Carolyn Maloney, Democrat of New York, said the investigation had “degenerated into a purely political exercise to tarnish the attorney general and the president in an election year.”

While a contempt citation has symbolic value and can taint reputations, it is not clear how much practical effect it would have. Congress has limited ability to enforce its own subpoenas since the Justice Department controls prosecution decisions about criminal contempt charges. Lawmakers can also file a civil lawsuit asking a judge to enforce it.

In 1998, the Republican-led oversight committee voted to recommend holding Attorney General Janet Reno in contempt for failing to turn over documents related to investigations of Democratic fund-raising, but the full House never voted on it.