Updated

Afghanistan has signed a deal with ex-Soviet neighbors Turkmenistan and Tajikistan to build a new railway linking the three nations.

Presidents Hamid Karzai of Afghanistan, Gurbanguli Berdymukhamedov of Turkmenistan and Emomali Rakhmon of Tajikistan inked the preliminary agreement Wednesday in the Turkmen capital.

The 400-kilometer (250-mile) railroad would link landlocked Afghanistan to a regional transport network, increasing the country's export potential. It would link the Afghan town of Akina-Andhoi, about 650 kilometers (400 miles) northwest of Kabul to Atamyrat in Turkmenistan and Pyandzh in Tajikistan.

The construction of the new railway is set to start in July in Turkmenistan. Turkmen workers will also build the Afghan segment of the railway.

A 75-kilometer (47-mile) line from Afghanistan into Uzbekistan began operating in December 2011.