A railway line linking Asian nations from Singapore to China - part of a broader 'Iron Silk Road' network stretching to Europe - will be completed by 2015.

Transport Minister Chan Kong Choy said the eastern link of the Trans-Asian Railway network would start from Singapore and travel north through Malaysia, Thailand, Cambodia and Vietnam before ending at Kunming in southern China.

Three sections of the eastern link are waiting to be built in Cambodia and Vietnam, the state Bernama news agency reported.

Malaysia is to help Cambodia build a 45-kilometre stretch between Poipet on the Thailand-Cambodia border, and Sisophon in northern Cambodia, it said.

"For the 45 kilometre-long missing link between Poipet and Sisophon, the construction of the railway would start early next year, using the rail tracks donated by Malaysia," Chan said according to Bernama.

"The (Asian Development Bank) would be financing the construction work," he was quoted as saying at a Southeast Asian railway conference here.

Chan said the completion of that section would allow trains to travel from Singapore to Phnom Penh.

18,000km rail network

Eighteen Asian nations earlier this month signed a landmark agreement on the Trans-Asian Railway, also dubbed the 'Iron Silk Road' after the ancient trade route.

The proposed 81,000-kilometer network, first mooted by the United Nations back in 1960, would link capitals, ports and industrial hubs across 28 Asian countries all the way to Europe.

The network would connect trans-Asian railway networks with Russia and Mongolia in the north, Malaysia and Indonesia in the south, South Korea in the east and Turkey in the west.

Despite enthusiasm from many countries, progress has been slow over the past decades due to numerous challenges, including raising financing.

Continent-wide problems include switching between different-gauge tracks, where to stop, how to handle sometimes tricky quarantine and immigration paperwork, and how to safely ferry cargo and people across many borders.