Brazil on Monday opened tender offers to construct a high-speed rail line between Rio de Janeiro and Sao Paulo, but uncertainty still surrounds the bidding process for the roughly $20 billion project.
The construction plan, one of the country's most ambitious, calls for the rail link to be operating by 2016, when Brazil will host the Olympic Games.
The new train is set to travel some 500 kilometers (300 miles) between the two cities in around an hour and a half, for a cost of 200 reals ($125) in economy class.
The system was designed to accommodate the influx of visitors for the Olympics and relieving pressure on Brazil's overcrowded airports.
Bidding on the new line already has been postponed twice, in November 2010 and in April, at the request of the various consortiums and Brazil's National Agency of Terrestrial Transports, known as ANTT.
Bidders are expected to include France's Alstom and a Japanese consortium.
There may be other bidders from Italy, Germany, Spain, China and South Korea, according to ANTT.
The country's biggest public works companies, which would handle much of the construction and logistics with any international partners, already had told the government they would not be bidding on Monday.
Despite the resignation last week of the country's transportation minister on corruption allegations, the government of President Dilma Rousseff has continued with the bidding process.
Copyright Agence France-Presse, 2011