With menacing firepower massed around the country, Pentagon sources say the US is also considering airdropping transistor radios to allow Afghan citizens to hear broadcasts produced by the State Department and psychological operations units.
The broadcasts would emphasise that the Afghan people are not the enemy of the US and are not the targets of military action.
The United Nations is stepping up its efforts to help the millions of Afghans threatened with hunger and homelessness, but the Taleban have yet to respond to requests to ease restrictions on relief work.
About 500 tonnes of food a day has entered Afghanistan in the past week, but that falls far short of the 52,000 tonnes a month needed to feed an estimated six million people dependent on foreign aid.
Diplomatic preparations for a military strike took a step forward when Pakistan said Osama bin Laden was probably behind the suicide plane attacks on New York and Washington.
Pakistan said it had seen enough evidence to justify putting bin Laden on trial. But it still wants Washington to publicly release details before an attack.
British Prime Minister Tony Blair was due to meet Pakistan's military ruler, Pervez Musharraf, overnight after talks in Moscow yesterday with Russian President Vladimir Putin.
Today, Blair will meet Indian Prime Minister Atal Behari Vajpayee.
Analysts say it is unlikely Washington will launch any operation against bin Laden or the Taleban until Blair and Rumsfeld have left the area - giving some breathing space to Afghanistan's rulers.
The regime's isolation was underscored by Pakistan's saying it no longer had any "diplomatic or other presence" in Afghanistan.
The Taleban leader, Mullah Mohammad Omar, appeared unmoved by Pakistan's shift and said behaviour by officials in Islamabad served to underscore that the Taleban took orders from no one.
Rumsfeld played down the role of military strikes, saying there was only a "small" chance that terrorists would be killed.
"The chance of any military action affecting any single terrorist, it seems to me, is small, which is why the President has said this is an effort which would have to be sustained over a long period of time," he said after meeting Egyptian President Hosni Mubarak.
The world's nervousness about the ongoing terrorism threat was underlined after a Russian airliner carrying at least 76 people from Israel exploded and plunged into the Black Sea.
Amid fears that the tragedy was the work of terrorists, Israel suspended takeoffs from its main airport and the White House went on high alert.
US authorities have now arrested 150 terrorist suspects linked to bin Laden's network. A further 350 people have been detained on various charges after closed hearings.
Map: Opposing forces in the war against terror
Afghanistan facts and links
Full coverage: Terror in America
