* Asian loans sought for $1.5-2 billion railway to boost trade
* Work on three-country route could start in July
* North-South rail route to Persian Gulf via Iran to open in May
By Marat Gurt
ASHGABAT, March 20 (Reuters) - The leaders of Afghanistan, Tajikistan and Turkmenistan invited Asian financial institutions on Wednesday to help fund construction of a regional railway to boost trade links for the three landlocked states.
The project, estimated at between $1.5 billion and $2.0 billion, aims to lay a line of around 350-400 km (220-250 miles) linking the neighbours' existing rail networks to other parts of Eurasia.
"It would be great if the Asian Development Bank, the Islamic Development Bank and Japan could take part in financing," said Tajik President Imomali Rakhmon, who signed a memorandum of understanding in the Turkmen capital Ashgabat.
Both banks have been providing funding for another rail link in the region, a North-South corridor linking oil-rich Kazakhstan and the Persian Gulf that is due to open in May.
Co-signatory Kurbanguly Berdymukhamedov, the Turkmen president, said that if international lenders provided joint financing for the new line, Turkmenistan would be ready to finance the stretch on its territory.
Berdymukhamedov, who wields virtually unlimited power in his desert nation of 5.5 million, said construction of the line - stretching from the town of Akmurad in Turkmenistan to Andhoi in Afghanistan - could start as soon as this July.
"This (project) will serve the common good of our three nations," Afghan President Hamid Karzai said.
Afghanistan's economy has been devastated by decades of foreign occupation and civil war, and Tajikistan, the poorest of the ex-Soviet nations, is still overcoming the aftermath of a 1992-97 civil war.
Turkmenistan, which holds the world's fourth largest reserves of natural gas, has been involved in the North-South corridor line since 2007, building the 311-km (194-mile) stretch to neighbouring Iran.
That line had been due for completion by September 2012. (Reporting by Marat Gurt; Writing by Dmitry Solovyov; Editing by John Stonestreet)