The air base facility leased to the United States at Kyrgyzstan's Manas airport is the number one strategic asset of the resource-poor Central Asian nation and for years has been a cause of tense negotiations with Washington.
A routine flight of a KC-135 Stratotanker US military refuelling plane from the base ended in tragedy when it crashed outside Bishkek Friday. The cause of the disaster was not immediately clear.
The base, which both sides now prefer to term a transit centre, is a key hub for transporting supplies, fuel and troops for the coalition military campaign in nearby Afghanistan.
It has also proved a highly useful source of foreign currency for Kyrgyzstan, with successive governments vying to win as much value as possible from the asset.
Manas, which hosts about 1,500 US troops and contractors and a fleet of the KC-135 refuelling tanker aircraft, operates round-the-clock, with planes transporting thousands of troops and hundreds of tonnes of cargo every month.
The recent history of the lease has been tumultuous and as things stand, Bishkek is expecting US military forces to exit in 2014.
Kyrgyzstan's former president Kurmanbek Bakiyev -- ousted from power in in a bloody uprising in 2010 -- threatened to cancel US access to the base entirely in 2009.
But Washington secured a new deal by agreeing to triple the rent paid to Bishkek. The United States now pays around $60 million a year for use of the air field, up from an earlier annual fee of about $17 million.
Incumbent President Almazbek Atambayev -- keen to strike a careful balance between Moscow and Washington -- has said Bishkek is prepared to host the base until the current lease expires in 2014 but then wants to US military to go.
Atambayev has said hosting the base is too much of a security risk for Kyrgyzstan that exposes it to the risk of attack by US foes like Islamic militants.
Instead the government wants to turn Manas into a full civil aviation hub for passenger planes, leaving the door open for a degree of potentially lucrative logistics cooperation with the United States.
The decision whether to extend the agreement will be taken at the end of May, leaving the Kyrgyz government a few weeks to decide whether to switch its position once again.
Landlocked Kyrgyzstan is currently the only nation in the world to host both Russian and US bases.
By contrast, Russia last year agreed a deal with Kyrgyzstan that will allow Moscow to keep its Kant military base in the country until 2032.