Bolivia's Senate has approved a bill that clears the way for Russia's Gazprom to explore for natural gas in the Azero block in partnership with France's Total.

Under the terms of the 40-year contract Gazprom and Total signed with Bolivian state-owned energy company YPFB, the two multinationals agreed to invest some $130 million to explore the more than 700,000-hectare (2,700-sq.-mile) block.

The bill will next be voted on in Bolivia's lower house.

The Azero block, in which YPFB will have a 55 percent stake in the event of a hydrocarbon discovery and Gazprom and Total will hold the remaining 45 percent, encompasses 785,625 hectares in the southeastern Bolivian provinces of Santa Cruz and Chuquisaca.

The first phase of the contract involves the exploration of Azero and will include magneto-telluric surveying and the drilling of two wells.

The accord between Gazprom and Total and YPFB marks the first foray by a Russian company into the Andean nation's gas sector.

A dozen multinational companies, including Spain's Repsol, Brazil's Petrobras and British Gas, already operate in Bolivia, mainly developing natural gas reserves for export to Brazil and Argentina.

In August, Russian state-controlled energy firm Rosneft expressed interest in investing in the exploration and development of hydrocarbon reserves in Bolivia.

Representatives of Rosneft and YPFB are expected to meet in October to discuss the possibility of the former operating some production areas. EFE