Mexico abruptly withdrew on a multi-billion-dollar tender that it had awarded to a Chinese-led consortium to build the country's first bullet train.
The China Railway Construction Corp had won the contract on Monday after submitting the only bid for the 210-kilometre (130-mile) railway between the capital Mexico City and the central manufacturing hub of Queretaro.
But President Enrique Pena Nieto decided "moments ago to revoke the November 3 ruling and restart" the bidding process, Transport Minister Gerardo Ruiz Esparza told the Televisa network.
The deal was revoked to avoid "any doubts about the legitimacy and transparency" of the bidding process after only one group participated, the minister said.
Pena Nieto made the surprise decision three days before flying to China for an Asia-Pacific Economic Cooperation (APEC) summit and a two-day state visit in his latest effort to forge closer ties with the Asian powerhouse.
The high-speed rail project is part of Pena Nieto's plan to bring back passenger trains to Latin America's second-biggest economy.
The Chinese-led group, which includes Mexican firms, was the only one to make a proposal by the October 15 deadline to enter a bid.
The transport ministry said at the time that 16 companies decided against making a proposal, including industry giants Mitsubishi of Japan, Alstom of France, Bombardier of Canada and Siemens of Germany.
