But in remarks to reporters after his meeting with Bush, Aziz spoke only of his country's cooperation with the United States in what Bush calls the war against international terrorism.
"We want to fight terrorism in all its forms and manifestations. There is no good terrorist or bad terrorist, and terrorism knows no borders. So our coalition with the United States in fighting terrorism is very important to all of the world and all of civil society."
Words Of Thanks For U.S. Aid
Pakistan and its leadership -- including its president, General Pervez Musharraf -- have been under pressure from the United States to help defeat Al-Qaeda since the attacks of 11 September 2001. Many Pakistanis have expressed resentment of the alliance.
That resentment softened after the United States offered massive relief to the victims of the October 2005 earthquake that killed more than 80,000 people in Pakistan. But anger resurfaced after the missile strike on 13 January.
At the White House, Aziz sought to focus his attention on his country's gratitude for the U.S. aid.
"We really appreciate what has been done, and it will help restore the lives of the people who have been impacted by the earthquake. A sense of caring and sharing always builds a better relationship between countries, and that's what we are seeing between Pakistan and the United States," he said.
Bush, too, avoided mention of the missile strike and announced that he would be visiting Pakistan and India in March.
A White House spokeswoman said details of Bush's trip to the Asian subcontinent aren't yet known.
Strategically Important Friends
Like Aziz, Bush also spoke of cooperation between the United States and Pakistan.
"I think the relationship with Pakistan is a vital relationship for the United States, and I want to thank the prime minister and thank the president for working closely with us on a variety of issues," Bush said. "We're working closely to defeat the terrorists who would like to harm America and harm Pakistan."
Since the missile strike, Pakistanis have been mounting anti-U.S. demonstrations. The U.S. military has not publicly acknowledged the attack, but unconfirmed reports shortly after the strike said it was launched by the CIA against suspected Al-Qaeda militants.
Although the attack did not kill al-Zawahri, Musharraf said on 24 January during a visit to Oslo, Norway that there is preliminary evidence that some Al-Qaeda members were killed in the raid. But he stressed that the evidence is not yet conclusive.
Despite fluctuations in the Pakistan-U.S. relationship, it remains strong, if only because of their mutual needs, according to Frederic Grare, a visiting scholar at the Carnegie Endowment for International Peace, a policy research center in Washington.
Grare told RFE/RL that the United States needs Pakistan for its help in defeating Al-Qaeda and for access to remote areas in Pakistan where Al-Qaeda members are believed to be hiding. Pakistan needs the United States for the aid it provides, he says.
But he adds that there are limits to this mutual need.
"Why do I say limits? Because it also implies that it's not necessarily in Pakistan's interest to go too far in this war on terror, at least not too quickly," says Grare. "Because as long as there's something to trade -- Al-Qaeda members [in exchange for U.S. aid] -- the relation will be lasting."
Grare says some in the Pakistani government fear that the relationship between the two countries may end, or at least become less important, if Al-Qaeda is finally broken up. But he doubts that would happen because, as he says, the United States will always need an ally in South Asia.