Rio de Janeiro, Apr 19 (IANS): Brazil's southeast city of Rio de Janeiro has opened bidding for two infrastructure projects in the lead-up to the 2016 Olympic Games, authorities said.

Mayor Eduardo Paes said Friday that the projects are part of the Diodoro Sports Complex that will host some 11 Olympic competitions, reported Xinhua.

The works, which are estimated to cost around $359 million, are expected to get underway in September and include the renovation of the complex also known as Sport City.

The projects also call for the construction of three new stadiums and the renovation of four others, as well as the installation of three temporary venues, whose delay has been a source of concern for the International Olympic Committee (IOC).

Acknowledging that preparing the bidding process took longer than expected, Paes said he expects the works to be concluded by the first half of 2016, as the games begin Aug 5.

He pledged, however, to have the projects finished in time for the events.

The Sport City will host nine different Olympic disciplines, including basketball, cycling, fencing, field hockey and rugby, as well as four disciplines as part of the Paralympic Games, which will take place Sep 7-18.

The complex, originally built by the city to host several events of the 2007 Pan-American Games, features a 15,000-seat multipurpose arena for basketball and artistic gymnastics, a 5,000- seat aquatic complex, and a 1,500-seat velodrome.

The 21st Olympic Games will gather the world's top athletes in 28 different sports in Rio from Aug 5 to 21.