US ambassador to Iraq, Ryan Crocker

Ambassador Crocker says U.S. officials are urgently trying to confirm Iraqi reports that the al-Qaida in Iraq leader has been killed, and he says if they are true it would, without question, be a significant and positive development.

But the U.S. envoy, in a video conference with reporters at the State Department, noted that al-Qaida attacks continued after its previous chief Abu Musab al-Zarqawi was killed in a U.S. air strike in June of last year, and that the death of al-Masri will likely be no different:

"I would not expect it to in any way bring to an end al-Qaida's activities in Iraq. We saw the organization adjust to death of Zarqawi," he said. "The sense I have of it is, that it is now a very decentralized terrorist effort, so while removing its current head would be a good and positive thing, I think we have to expect we'll need to continue dealing with further al-Qaida attacks."

The U.S. envoy said al-Qaida has mounted a surge of suicide car bomb attacks to try to counter the American troop surge and Baghdad security plan.

Crocker, a veteran of previous Baghdad postings who has been in a current job for a month now, said he found the physical and psychological damage of the latest bombings "sobering."

But he said sectarian killings in the capital have been declining in recent weeks and that bombing campaign does not mean the security plan has failed.

The U.S. ambassador is due to join Secretary of State Condoleezza Rice in Sharm el-Sheikh Egypt Wednesday for two international meetings on Iraq.

Some 60 countries will take part in a ministerial level meeting of the international Compact with Iraq expected to focus on debt relief for the struggling country.

The second will bring together world powers and neighbor countries of Iraq including Syria and Iran, both of which have been accused by the United States of helping foment Iraq violence.

Crocker said the role of Iraq's neighbors will have a "crucial" bearing on the country's future.

"Clearly what we want to do is see the neighbors, all of the neighbors, commit themselves to constructive roles and not destructive ones. It's obviously something we can't predict at this point," he said. "But I'm encouraged by the fact that all Iraq's have agreed that they will be at the table, at a senior level, in Sharm El-Sheikh, so this discussion can proceed."

U.S. officials have not ruled out interaction between Secretary Rice and her Iranian and Syrian counterparts. President Bush said Monday Rice would be polite but firm in raising U.S. concerns about their activities in Iraq.