Iraq (search) urged the world's nations Friday to stand up to "blackmail" and keep their diplomatic missions in the country despite a claim by an Al Qaeda wing that it killed Egypt's top envoy.

Al Qaeda in Iraq (search) claimed in a Web posting that it had killed the Egyptian diplomat, Ihab al-Sherif, and warned it would go after "as many ambassadors as we can" to punish countries that support Iraq's U.S.-backed leadership.

Saad Mohammed Ridha, the head of Iraq's diplomatic mission in Cairo (search), told The Associated Press that Egypt's foreign ministry informed him late Thursday that the mission would close temporarily and the staff was recalled.

An Egyptian official in Cairo also said Egypt would temporarily close its mission in Iraq and has recalled its staff — although there was no sign Friday that any of the Egyptians were leaving.

Iraqi government spokesman Laith Kubba said he hadn't been informed that Egypt intended to recall its diplomats, but urged other countries not to be intimidated.

"If the rest of the diplomatic missions from Europe and the neighboring countries give in, this means that all the capitals of the world will be subjected to blackmail," Kubba said Friday.

Shiite and Sunni clerics, speaking at Friday prayers, condemned al-Sherif's killing.

"We reject any attack against any diplomat because attacking the diplomats is an act that doesn't serve our cause," said Sheik Ahmed Abdul Ghafour al-Samarie of the Association of Muslim Scholars at Baghdad's Um al-Qura mosque during Friday prayers.

A Shiite sheik also denounced the apparent killing and made a brief reference to Thursday's London's explosions that killed more than 50 people in the city's transit system.

"The explosions that occurred in London were barbaric acts by the terrorists," said Sheikh Jalal al-Deen al-Saghir at the Shiite Baratha mosque in Baghdad.

The announcement from Iraq's most feared terror group about al-Sherif appeared on an Al Qaeda-linked Web site and featured a brief video showing him wearing a polo shirt. The video did not show his death, but the statement promised more details later. Al Qaeda in Iraq, led by Abu Musab al-Zarqawi, normally releases videos of its victims' deaths.

The Iraqi foreign ministry offered condolences for the "assassination" and an Egyptian diplomat who spoke to Egyptian reporters in Cairo said the government was sure al-Sherif was dead "from our own means." He spoke on condition of anonymity and did not elaborate.

News of the killing marked a dramatic escalation in a campaign to discourage Arab and Muslim governments from sending ambassadors and strengthening ties with Iraq, as Washington wants. Last month, Iraqi Foreign Minister Hoshyar Zebari announced that Egypt would be the first Arab country to upgrade its diplomatic representation by appointing a full-fledged ambassador.

Despite the upsurge in attacks against diplomats, violent incidents in the Iraqi capital have declined sharply since Iraq's U.S.-backed forces launched an operation against insurgents in the city six weeks ago.

In a video-teleconference interview from Baghdad with reporters at the Pentagon, Maj. Gen. William G. Webster Jr. said car bombings had dropped from 14 to 21 a week in May to about seven or eight a week now.

But Webster said it was "very difficult to know" whether the insurgency has been broken.

In Cairo, Egyptian President Hosni Mubarak insisted his country will continue to support Iraq.

"This terrorist act will not deter Egypt from its firm position in support of Iraq and its people," the statement said. Al-Sherif "lost his life at the hands of terrorism that trades in Islam but knows no nation and no religion."

Al-Sherif, 51, was seized Saturday in Baghdad. Three days later, gunmen fired on senior envoys from Pakistan and Bahrain, two Muslim nations with close ties to the United States, in apparent kidnap attempts.

In its latest statement, Al Qaeda said it did not announce al-Sherif's kidnapping until after the subsequent attacks "to be able to capture as many ambassadors as we can."

Iraqi officials, meanwhile, sought to assure foreign governments that their diplomats would be safe. Officials said al-Sherif, a former deputy ambassador to Israel, was grabbed in a dangerous neighborhood while traveling without armed escorts.

Egypt's U.N. ambassador asked the U.N. Security Council on Thursday to urgently address the issue of protecting diplomats in Iraq. Ambassador Maged Abdelaziz said the council should address the issue "in a manner which would secure the lives of those diplomats, not only of Egypt but of other countries who have been subject to such brutal attacks in the past few days."

In violence Friday, a roadside bomb killed a U.S. soldier and wounded three in Balad, about 50 miles north of Baghdad, the military said. The soldiers belonged to the 29th Brigade Combat Team.

Separately, a homicide car bomber hit an Iraqi army convoy in Fallujah, some 40 miles west of Baghdad, witnesses said. The remains of human flesh and mangled cars were seen, but police officials said they had no details about the attack.

Meanwhile, a follower of radical Shiite cleric Muqtada al-Sadr said the U.S.-led foreign presence is endangering Iraqis.

"I want to inform you that one of the brothers proposed launching a campaign to collect one million signatures demanding the withdrawal of American troops," Sheik Abdul Zahra al-Sowaiedi said during prayers in the eastern Baghdad slum of Sadr City.

Al-Sadr, who opposes the U.S.-led foreign presence in Iraq, has recently taken on a higher public profile after emerging from months of hiding following clashes last year between U.S. troops and his militiamen.

Speaking in Amman, Jordan, former Iraqi Prime Minister Ayad Allawi urged the United States to produce a roadmap to end the crisis in Iraq, and warned in comments published Friday that the deteriorating situation could impact neighboring countries.

"If the situation continues to deteriorate, the concept of national unity will weaken," Allawi said. "This will have a great impact on Iraq and will move to the neighboring countries, Europe and America," he said.