In military doublespeak, almost 5,000 troops of the U.N. Protection Force are trapped at their patrol sites by "an administrative matter."
In reality, the peacekeepers and all other foreigners here are being held hostage by Bosnian Serb rebels who have been angered by NATO air strikes and emboldened to test the limits of the West's newfound resolve.
The U.N. commander for Bosnia-Herzegovina, British Lt. Gen. Michael Rose, has refused to make an issue of the blockade shackling his troops, gambling that, by brushing off the retaliation, he can compel the Serbs to back down without their losing face.
While Rose's career as a special forces officer is replete with successes in such volatile, high-stakes faceoffs, diplomats and aid officials more familiar with the psychology of the Serbian rebellion fear the general's business-as-usual strategy may be playing straight into the rebels' plans.
To the question of who can hold out longer, the hostage peacekeepers or the disgruntled Serbs, few here doubt the ability of the rebel gunmen to bear hardship, especially when buoyed by the propagandistic message of their leaders that the West is afraid to strike again.
Immediately after bombs were dropped on Serbian tank units attacking the U.N.-designated "safe haven" of Gorazde, Rose and other top U.N. officials took pains to characterize the air strikes as moves to protect U.N. troops rather than the embattled and outgunned people of the mostly Muslim enclave of Gorazde.
All top U.N. officials here have expressed the hope that no further resort to "air support" will be needed; Rose ruled it out completely as a means of breaking the blockade of nearly half his troops.
Since the air strikes Sunday and Monday, the rebels have detained U.N. troops and observers and isolated at least 4,700 soldiers by mining their patrol sites, sealing off Sarajevo and posting gunmen outside the barracks of smaller units to keep the soldiers under house arrest.
Forces loyal to Bosnian Serb nationalist leader Radovan Karadzic pulled back heavy weapons in February after the North Atlantic Treaty Organization threatened to bomb any artillery left within 12 miles of the capital. But the rebels, still armed with machine guns, grenades, mines and mortars, remain deployed in a strangling cordon around the city.
There was a sharp increase in small-arms fire late Wednesday, and at least four large-caliber shell impacts underscored the rebels' anger at having been targeted for air strikes.
Karadzic and the hard-line Bosnian Serb military chief, Gen. Ratko Mladic, have proclaimed the U.N. mission an enemy of the Serbian people and threatened to shoot down NATO planes.
"All our agreements so far, and our good manners which we displayed out of our trust in you, are now a thing of the past, since we are forced to regard the behavior of (the U.N. peacekeeping troops) as a potentially hostile force," Karadzic wrote in a letter to U.N. Secretary General Boutros Boutros-Ghali.
After accusing the international community of intervening on behalf of the Muslim-led government, he informed the U.N. chief: "You will understand that we can no longer cooperate with this (U.N. force) command which ordered the bombardment." Karadzic sought to justify the blockade as necessary to contain an adversary.
Far from reacting with threats of further punishment, both military and civilian U.N. officials have allowed Serbian leaders in nearby Pale to call the shots as to whom they will talk with and what steps need to be taken to reopen peace talks.
After the commander of U.N. forces in the former Yugoslav republics, French Gen. Bertrand de Lapresle, and the chief U.N. civilian official, Yasushi Akashi of Japan, were rebuffed when they attempted to call on Karadzic on Tuesday, two mediators who earlier brokered a plan that would allow the rebels to keep half of Bosnia and one day join with a Greater Serbia were summoned back to the diplomatic fore.
The recall of European Union mediator Lord Owen and his U.N. counterpart, Thorvald Stoltenberg, risked sending a signal to the Serbs that they can dictate the terms of a settlement from their commanding position of having already conquered more than 70% of this country.
Some observers here, particularly those in Rose's command, see the brash statements and behavior as bluster. They count on time and the revised diplomatic roster to persuade the Serbs that their best interests will be if they resume negotiations on an overall peace settlement.
But others worry that banking on self-interest and logical behavior may be a formula for disaster in a war sparked by vitriolic propaganda, which has demonized all non-Serbs and created a nationalist mind-set that life for Serbs will be secure only in an ethnically pure state.
Serbian gunmen boast that they would rather be reduced to eating grass and living in squalor than share land and citizenship with the Muslims, Croats and Albanians who they claim endanger them throughout the former Yugoslav federation.
The handful of bombs dropped by NATO warplanes are unlikely to terrify the rebels into knuckling under at the paralyzed peace talks, one Western diplomat here noted.
On the contrary, he said, unless the United Nations and NATO are prepared to inflict serious damage on the Serbian war machine, an endless series of military adventures can be expected against the scattered and poorly protected Muslim enclaves.