Brazil has announced Rio de Janeiro will run against London as a candidate to host the 2012 Olympic Games.

The city was chosen over San Paolo, the national capital, by 23 votes to 10 in the Brazilian Olympic Committee.

Rio's mayor, Mayan Cesar, said he had expected his city to gain the nomination, but that the number of votes had surprised him. He estimated an investment of US$1.6billion would be necessary to prepare for the games.

As well as London, Rio will be competing against Moscow, New York, Paris, Madrid, Havana, Leipzig, and Istanbul.

The International Olympic Committee (IOC) will announce its choice for the 2012 games' host in Singapore on 6 July 2005.

IOC president Jacques Rogge spoke about Rio de Janeiro at a press conference in London yesterday.

Asked whether Brazil's bid may benefit from the fact the games have never been hosted on the south American continent before, Mr Rogge said he would not be 'double-guessing'.

He said: "My message is not to focus on this continental issue."

"The IOC is concerned first about the quality of the bid."

But he added: "When two bids are of the same quality, a continental location might play a role."