Defense Secretary William Cohen, Gen. Henry H. Shelton, chairman of the Joint Chiefs of Staff, and Sandy Berger, President Clinton's national security adviser, briefed senators privately on the Iraqi strike plans.
A defense official that spoke on condition of anonymity said the presentation was broad and did not get to the level of specific attack plans or even contingencies.
After the briefing, Sen. Kay Bailey Hutchison, R-Texas, said members were concerned whether U.S. forces could "achieve the results we are seeking."
Cohen, also speaking to reporters afterwards, said he outlined very clear goals of "degrading (Saddam Hussein's) weapons of mass destruction capabilities" and any threat of destabilizing the oil-rich region. He said time is running out and Clinton would decide when diplomatic efforts should end.
Prior to the briefing, Cohen outlined the same goals to the Senate Armed Services Committee but conceded that strikes on chemical or biological weapons manufacturing facilities would still leave Iraq in a position to reconstitute those facilities quickly.
"We should not raise unreasonable expectations about what can be achieved by air power alone," Cohen said. "I believe diplomacy is still the best way to resolve this issue."
House Speaker Newt Gingrich's office, meanwhile, issued a statement "obviously declining" Iraq's invitation for a congressional delegation to visit some of the palaces so far denied to U.N. weapons inspectors.
A day earlier, Saudi Arabia said Iraq bears responsibility if diplomacy fails to end the inspection impasse. But the Saudis stopped short of granting U.S. warplanes use of their air bases for possible strikes against Iraq.
In Egypt, Secretary of State Madeleine Albright met with President Hosni Mubarak, who has stressed the need for a diplomatic solution and has conferred in recent days with Arab leaders.
The United States has the unequivocal support of Britain in its approach toward Iraq.
British Prime Minister Tony Blair warned Saddam that Britain is prepared to use military strikes as soon as they are deemed necessary.
"Diplomacy is fast being exhausted," he said, echoing a sentiment Albright has been expressing since before her departure from Washington last week.
Blair also rejected suggestions that he risked alienating the Arab world.
"I think the Arab world appreciates the need to deal with Saddam Hussein. I would say the Arab world knows that very well," he said.
Blair has arrived in Washington for talks with President Clinton and other officials.
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