The agreement of Asian Development Bank (ADB) has approved a $160 million loan to modernize the operations and improve the efficiency of Sri Lanka Railways, the country's railway operator, by upgrading its infrastructure and technical capacity.This is ADB's first loan for Sri Lanka's railway sector, will be sign tomorrow, Transport Minister Arjuna Ranatunga said today.Adderssing a media conference held at the Temple tree Mr. Ranatunga added that this is the first occaition ADB has grant this kind of loan to the development of transwport sector.