A senior White House official said Sunday that President Obama wants to strike an “appropriate balance” in dealing with a Chinese dissident who fled house arrest last week and reportedly is under protection in the U.S. Embassy in Beijing.

Comments by John O. Brennan, Obama’s top counterterrorism adviser, were the closest the administration has come to confirming the whereabouts of dissident lawyer Chen Guangcheng and the difficulty the situation poses for U.S. policymakers.

The president tries to “balance our commitment to human rights” with continuing “to carry out our relationships with key countries overseas,” Brennan said on “Fox News Sunday.” “We’re going to make sure that we do this in the appropriate way and that appropriate balance is struck.”

Obama “has faced similar situations in the past in terms of this balancing requirement,” Brennan said, and he “will do whatever he thinks is in the best interest of the United States as well as the individuals involved.”

Both the U.S. and Chinese governments have studiously avoided confirming Chen’s whereabouts, adhering to uniform “no information” comments.

Mitt Romney, the presumptive Republican presidential nominee, said in a statement Sunday that he hopes the United States “will take every measure to ensure that Chen and his family members are protected from further persecution.” He said U.S. policy toward China must address human rights violations. “Our country must play a strong role in urging reform in China and supporting those fighting for the freedoms we enjoy,” he said.

The incident comes at a particularly dicey time for U.S.-China relations, on the heels of the appearance of a senior Chinese law enforcement official at the U.S. consulate in Chengdu with information that brought down a senior Communist Party boss, and on the eve of this week’s visit to Beijing by Secretary of State Hillary Rodham Clinton and Treasury Secretary Timothy F. Geithner for high-level talks.

Kurt Campbell, the State Department’s top diplomat for East Asia, appeared Sunday in Beijing on an unannounced trip, apparently to deal with the Chen situation in advance of Clinton’s arrival. The State Department declined even to confirm Campbell’s presence in the Chinese capital, although he was photographed at a Beijing hotel early Sunday.

Brennan made the rounds of three Sunday talk shows to mark the first anniversary of the U.S. Navy SEAL raid in Pakistan that killed al-Qaeda leader Osama bin Laden. Although the administration had indicated that U.S. security was on heightened vigilance against a terrorist attack to mark the date, Brennan said on ABC’s “This Week”: “At this time, we don’t see any active plot that is underway.”

Bin Laden’s death “made a tremendous difference,” he said. “It’s taken away the founding leader of that organization who was . . . a symbol of al-Qaeda’s sort of murderous agenda worldwide.”

Although that and numerous other gains have been made against the organization, he said, “I don’t look at it as a victory. I think . . . we have to destroy the organization. We have to take all of their operatives, their leaders, their training camps, take away their safe havens. And we’re not going to rest.”

Hosts on ABC, Fox and CNN’s “State of the Union” tried to get Brennan to respond to an Obama campaign video suggesting that bin Laden might be alive today had Romney been president. Sen. John McCain (R-Ariz.), a Romney backer, called the ad “a shameless end-zone dance to help [Obama] get reelected.”

Brennan repeatedly refused the bait. “I don’t do politics,” he told ABC. “I don’t do the campaign. I am not a Democrat or Republican. I’m a counterterrorism adviser to the president. All I know is that the president made the decision when he was given the opportunity to take a gutsy decision. . . . We’re safer today as a result.”