Russia has authorized the United States to use its airspace for flights carrying troops and military supplies to Afghanistan.
The deal, signed Monday at a U.S.-Russian summit in Moscow, permits up to 4,500 military flights a year - about 12 a day - carrying troops, arms, munitions, military vehicles and spare parts.
Senior U.S. officials say the flights will not be charged Russian transit fees and will not stop in Russian territory.
Moscow had previously limited U.S. shipments across its territory to non-military supplies carried by train.
The White House said the air transit agreement will save more than $130 million a year in fuel and other transit costs.
The two presidents also agreed to boost joint anti-terrorism and anti-crime measures, including cooperation in sharing financial intelligence in the fight against heroin trafficking.
Some information for this report was provided by AFP and AP.