"We do not have any guarantees that tomorrow we will not find ourselves face to face with these terrible terrorist forces and so we do not want to allow ourselves to be used by anyone," he said.
Earlier on Friday, a U.S. official said 1,000 U.S. light infantry were en route to Uzbekistan. "Troops from the 10th Mountain Division are on their way," the official said.
Expectations grew of U.S. and British military action in Afghanistan, whose Taleban rulers are harbouring Osama bin Laden blamed for the Sept. 11 suicide attacks on New York and Washington that left almost 5,600 people feared dead.
Uzbekistan had allowed the United States to use its airspace and was ready to "upgrade and step up" intelligence- sharing efforts, Karimov said.
In Washington, defence analysts said Karimov's public refusal to allow elite U.S. Special Forces troops to operate from Uzbek soil could present problems for a military strike.
But they suggested that humanitarian and search-and-rescue operations might be broadened with quiet approval from Tashkent.
"The announcement was not helpful on the surface because there aren't too many places where you can get special ops (operations) troops any closer. Pakistan is out. Iran is out. We don't know about Tajikistan," Ivo Daalder of the Brookings Institution told Reuters.
"But there is a gray area in which humanitarian and rescue missions might be expanded with the use of protective fighter jets," added Andrew Krepinevich of the Centre for Strategic and Budgetary Assessments. "That probably works to the benefit of the Uzbeks and to the United States."
A document was being drawn up to detail the agreement between the United States and Uzbekistan and would be made public to show that "we have no secret deals, no covert negotiations with the United States," Karimov said.
Asked what the United States had offered Uzbekistan in return for its assistance, Rumsfeld replied, "There have been no specific quid pro quos.
"The interest of the United States in Uzbekistan, it should be well understood, precedes the events of September 11," he said. "The interest of the United States is to have a long-standing relationship with this country and not something that's focused on the immediate problem alone."
Rumsfeld said earlier he saw similarities between the battle against terrorism and the Cold War that ended a decade ago.
"It undoubtedly will prove to be a lot more like a cold war than a hot war," Rumsfeld said on Thursday during a tour that has also taken him to key U.S. allies in the Middle East, including Saudi Arabia, Oman and Egypt.
"The important thing is to see that we put enough pressure on the terrorist and the people who harbour terrorists through a variety of means over a sustained period."
The aim was to force terrorists to alter their behaviour, go on the run, lose financing and attract fewer recruits.
Rumsfeld said the conflict would resemble the Cold War with communism, which he said "did not involve major battles, it involved continuous pressure, it involved cooperation by a host of nations, it involved the willingness of populations in many countries to invest in it and to sustain it."
Rumsfeld was on his way to Turkey on Friday before returning to the United States.
Defence Undersecretary Douglas Feith, who has accompanied Rumsfeld on this trip, planned to stay in the Gulf region for visits to Jordan, Kuwait, the United Arab Emirates, Qatar and Bahrain.
- REUTERS
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