Emmanuel Angeles, CDC president and chief executive officer, identified three of the firms as the US-based First Asia Transit Partners, the First China Construction Corp. and MACE of the United Kingdom.
Angeles said a Japanese firm, which he did not identify, might also be considered since the government is working out funding from the Japan Bank for International Cooperation for the project.
"Id like to see the project finished before 2004 because it is a vital requirement to fully transform the Macapagal airport into a premier gateway," Angeles told reporters.
The railway project was proposed way back in 1994 when former President Fidel Ramos issued an executive order declaring Clark as "the future site of the countrys premier international airport."
The project was dropped from the priority list of the National Economic Development Authority (NEDA) for funding from Japans Obuchi Fund during the Estrada administration, but was revived recently by the Arroyo administration.
Angeles said funding for the railway project could come from the $8.6 billion in overseas development assistance that Japan allocates annually for the Philippines.
Earlier, Presidential Assistant for North Luzon Renato Diaz appealed to local government officials to help relocate thousands of families living along the old railroad tracks of the Philippine National Railways, particularly in Pampanga and Bulacan.
He said the relocation of these families is one of the conditions for the release of Japanese funding for the project.
Meanwhile, Angeles said the CDC, the Bases Conversion and Development Authority, AsiaKonstrukt and the National Development Corp. (NDC) are now holding discussions for the reopening of the moth-balled 60-hectare Expo Pilipino here.
Angeles said he met with AsiaKonstrukt president Ed Angeles in the US and the latter informed him that officials of Disneyland are interested in investing in the Expo Filipino.
He said he wants the Expo Pilipino to reopen on Feb. 14 next year.
Angeles was a member of President Arroyos entourage in her recent working visit to the US.
The controversial Expo Pilipino, built at a cost of about P3.2 billion, was ordered shut down by former President Joseph Estrada due to heavy losses.