Deaths unavoidable, says NATO chief

Rescue workers continue to search for survivors amid the rubble of the World Trade Center

VIENNA, Austria -- NATO's chief allied commander says more deaths would be unavoidable as part of a military response to terrorist attacks in New York and Washington.

"We cannot be in the mind set of a zero-casualty operation," General Joseph Ralston told a news conference in the Austrian capital, Vienna.

"We have to get our missions done," he said. "We will take all prudent measures to protect our people as best we can. But there will be casualties. That is a necessary part of any military operation."

Ralston was in Austria to meet government ministers and observe a NATO "Partnership for Peace" exercise involving about 1,500 soldiers from 20 different countries.

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The general insisted the mission would go on despite the risks and said retaliation would require a sustained effort over time, The Associated Press news agency reports.

"We must all recognise that this is not a risk-free operation that we are embarking upon," he said. "I don't believe people expect a single strike and that will be the end of the problem."

The U.S. Air Force general said he was heartened by the response of Washington's NATO partners to its call for support.

"Let me say very unequivocally and up front -- I am not in any way, shape or form disappointed in the level of support that has been offered by NATO allies," Ralston said.

"I have absolutely nothing but praise for the members of the alliance and other members of the European Community who have come forward with very substantial support," he added.

The general said offers of support had been both for direct military action and other supporting actions.

"This is a sustained effort over a long period of time by the entire international community -- and not just military. We are talking about economic, political, diplomatic as well as military," Ralston told the conference.

Ralston told Reuters he was satisfied with current U.S. troop levels in Europe, where some 115,000 personnel -- eight percent of Washington's active-duty military strength -- are based.

"But if more troops are needed, then we certainly have the means to get those troops," he said.

German President Johannes Rau has called on the United States to respond to the attacks "with civil means," AP reports.

A statement from the Italian Defence Ministry has also "categorically excluded" the possibility of an "extraordinary call to arms" in Italy, the news agency reports.