British soldier in Afghanistan
The reopening of land routes over Pakistan will help NATO to supply its troops in Afghanistan. Reuters

An agreement signed by the United States and Pakistan on Tuesday has determined some logistical details concerning NATO's usage of Pakistan land routes to transfer supplies to troops in Afghanistan.

The Memorandum of Understanding includes an agreement for the United States to release more than $1 billion in military aid to Pakistan, reported Voice of America. In exchange, NATO will be more easily able to transport necessary supplies to its troops in neighboring Afghanistan.

According to NATO, more than 100,000 foreign troops from over 50 different nations are currently serving in Afghanistan. These forces are working to equip and train the Afghan National Security Forces, which has about 164,000 members, so that it can maintain order and defend Afghanistan against insurgencies and other threats.

NATO hopes to officially end its mission there in 2014, though some troops will remain in Afghanistan as a stabilizing presence indefinitely.

Until last month, Pakistan refused to allow NATO to transport supplies via its overland routes into landlocked Afghanistan. The routes were shut down by Pakistan last November in a retaliatory measure after U.S. airstrikes inadvertently killed 24 Pakistani troops.

NATO has meanwhile used more expensive and time-consuming means of getting supplies into Afghanistan, including long overland routes that run from the Black Sea through Siberia and Central Asia.

A formal announcement of the reopening was made on July 3, after U.S. Secretary of State Hillary Clinton called Pakistan to express deep regrets over the November incident.