“He maintained that that was his view and, by the actions he has taken as president, feels that it was the right approach and continues to feel that way,” he added.

During the 2008 presidential campaign, then-Senator Obama said that he would order action against Bin Laden or other senior Al-Qaeda leaders inside Pakistan if the country's leadership “is unable or unwilling to act,” AFP said.

Senator John McCain, the Republican candidate for president, accused Senator Obama at the time of effectively threatening an allied nation and said that if a target came into view, “you work with the Pakistani government.”

US officials have said that they gave no prior notice to Pakistan before Sunday’s daring raid, in which special forces killed the world’s most wanted man at a mansion near the country's top military academy in Abbottabad.

Leon Panetta, Director of Central Intelligence, said that the United States chose not to alert Pakistan of the operation on its soil for fear that officials would alert the Al-Qaeda chief.

Pakistan has been on the defensive since Sunday’s attack, with Prime Minister Yousuf Raza Gilani saying that the United States and other countries shared the blame for not finding bin Laden sooner, according to AFP.

The United States has an uneasy partnership with Pakistan, which supported Afghanistan’s hardline Taliban regime until the September 11, 2001 attacks by Al-Qaeda.

Pakistan has often voiced anger at US operations against Al-Qaeda targets on its soil, particularly strikes with unmanned drones which the government says make a mockery of its sovereignty.

The United States carried out more than 100 drone strikes in Pakistan last year, killing more than 670 people, according to an AFP tally.

While it is not yet certain who will replace Osama Bin Laden to lead Al-Qaeda, Mr. Panetta said early Wednesday that whoever takes his place will become America’s new public enemy number one.

Mr. Bin Laden’s deputy, Ayman al-Zawahiri, is expected in some circles to take over, but it is not clear how soon that will happen. Dr. Zawahiri may well be more concerned for his own safety after US special operations took out the Al-Qaeda chief in a daring raid on Sunday.

“He's moving up very fast on the list,” Mr. Panetta told CBS television's “Evening News with Katie Couric” in referring to Dr. Zawahiri, according to Agence-France Presse.

His remarks were made as US lawmakers showed growing incredulity—and anger—that Bin Laden could have lived so close to Pakistan’s capital city of Islamabad without the administration of President Asif Ali Zardari not knowing. Some Congressmen have started clamoring for putting an end to the aid of more than $1 billion that the US gives Pakistan annually to fight terrorism.

Mr. Panetta said that until a new Al-Qaeda leader is formally appointed, the US expects to take advantage of the situation.

“We think that'll give us some opportunities to be able to continue to attack them in the confusion and debate that they’re going to go through as to who ultimately replaces Bin Laden,” he said. “But I can assure you, whoever takes his place, he will be number one on our list.”

Mr. Panetta said that there was no question that the US will ultimately release a photo showing Mr. Bin Laden dead.

“The government obviously has been talking about how best to do this, but I don’t think there was any question that ultimately a photograph would be presented to the public,” Mr. Panetta said, according to Reuters.

Asked by Reuters about the remarks, a White House spokesman said no decision had been made about releasing images of Bin Laden’s corpse.

Mr. Bin Laden’s hideout in a large compound in the cantonment of Abbottabad, just north of Islamabad, has led to widespread speculation that the Pakistani government had been aware of the Al-Qaeda leader’s whereabouts.

But Mr. Panetta said the US government does not have any intelligence indicating that “Pakistan was... aware that Bin Laden was there, or that this compound was a place where he was hiding.”

Noting that the compound was close to an elite military academy and that Bin Laden had been living there about five years, Mr. Panetta nonetheless pressed Islamabad to provide more answers.

“I just think they need to respond to the questions about why they did not know that that kind of compound existed,” he said, according to AFP.

Asked whether Pakistan should be declared a terrorist state, Mr. Panetta acknowledged that the US-Pakistani relationship is a “very complicated and difficult” one, but warned the ties should not be severed.

“Look, we are virtually conducting a war in their country going after Al-Qaeda,” he said. “And at the same time, we’re trying to get their help in trying to be able to confront terrorism in that part of the world.”

“And they have given us some help, and they have given us some cooperation,” Mr. Panetta said.