The United States expects Yemen to cooperate with more counter-terrorism operations like the one that killed Anwar al-Awlaqi, regardless of the political fate of the country's embattled president, Defense Secretary Leon Panetta said.
"There are a lot of people in the leadership there concerned about Awlaqi, concerned about terrorism," Panetta told reporters on his plane en route to Israel.
"We have developed over the years a relationship where we worked together, we shared intelligence, and we focused on some common targets there as well.
"And I think that will continue to be the case regardless of what ultimately happens with president (Ali Abdullah) Saleh," said Panetta, who served as CIA director until taking over as Pentagon chief in July.
The Central Intelligence Agency and the US military long relied on Saleh as a crucial partner in battling Al-Qaeda militants such as the American-born cleric Awlaqi, who was killed in an air raid on Friday.
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But the US administration has called on Saleh to peacefully hand over power after months of street protests.
The killing in Yemen Friday of Al-Qaeda's Awlaqi in an air raid was hailed by US President Barack Obama as a "major blow" to terrorists.
But the White House refused to confirm reports that CIA drone aircraft and military units had mounted the raid, keeping a veil of secrecy over US anti-terror operations.
Panetta said he could not confirm whether master Al-Qaeda bomb-maker Ibrahim Hassan al-Asiri also was killed in the strike along with Awlaqi, amid media speculation about Asiri's fate.
"I don't have any direct information to confirm that," he said.
Unrest that has erupted in Yemen and across the Arab world will be high on the agenda during Panetta's trip this week to the Middle East and to Brussels for a meeting of NATO defense ministers.
Panetta was due to hold talks in Israel on Monday with Israeli and Palestinian leaders before heading to Cairo.