Venezuelan president Hugo Chávez is poised to launch a bid to transform the global politics of oil by seeking a deal with consumer countries which would lock in a price of $50 a barrel.

A long-term agreement at that price could allow Venezuela to count its huge deposits of heavy crude as part of its official reserves, which Caracas says would give it more oil than Saudi Arabia.

"We have the largest oil reserves in the world, we have oil for 200 years." Mr Chávez told the BBC's Newsnight programme in an interview to be broadcast tonight. "$50 a barrel - that's a fair price, not a high price."

The price proposed by Mr Chávez is about $15 a barrel below the current global level but a credible long-term agreement at about $50 a barrel could have huge implications for Venezuela's standing in the international oil community.

According to US sources, Venezuela holds 90% of the world's extra heavy crude oil - deposits which have to be turned into synthetic light crude before they can be refined and which only become economic to operate with the oil price at about $40 a barrel. Newsnight cites a report from the US Energy Information Administrator, Guy Caruso, suggesting Venezuela could have more than a trillion barrels of reserves.

A $50-a-barrel lock-in would open the way for Venezuela, already the world's fifth-largest oil exporter, to demand a huge increase in its official oil reserves - allowing it to demand a big increase in its production allowance within Opec.

Venezuela's oil minister Raphael Ramirez told Newsnight in a separate interview that his country plans to ask Opec to formally recognise the uprating of its reserves to 312bn barrels (compared to Saudi Arabia's 262bn) when Mr Chávez hosts a gathering of Opec delegates in Caracas next month.

Venezuela's ambitious strategy to boost its standing in the global pecking order of oil producers by increasing the extent of its officially recognised reserves is likely to face opposition. Some countries will oppose the idea of a fixed price for the global oil market at well below existing levels. Others are unlikely to be happy with any diminution of their influence over world oil prices in favour of Venezuela.

Caracas's hopes for an increase in its standing would be a far cry from the days when Mr Chávez came to power after years of quota-busting during which Venezuela helped to keep oil prices down. "Seven years ago Venezuela was a US oil colony," said Mr Chávez.

As he seeks to bolster his country's standing on the world stage, the Venezuelan president has also introduced radical changes to the domestic oil industry. Last Friday his government announced that 17 oil companies had agreed to changes which will see 32 operating agreements become 30 joint ventures that will give the government greater say over the country's oil industry.

The original deals were signed in the 1990s as part of a drive to attract more investment into the country's oil industry. However Mr Chávez said the deals gave foreign companies too much and the government too little. Under the new arrangements state-run Petroleos de Venezuela will hold 60% of the joint ventures. "Now we are associates and this commits us to much more ... it's no longer a contract for doing a service, it's a strategic alliance," Mr Chávez told the companies that signed up.

The new arrangements were not universally welcomed by the oil companies. Exxon Mobil and the Italian energy company Eni have refused to sign up to the new arrangements.

Mr Chávez, a former paratrooper who has survived several attempts to oust him and who faces re-election in December, regards Venezuela's oil revenues as crucial to his plans to fight poverty. Critics accuse him of squandering the country's oil wealth on improvised social programmes.

The Venezuelan president used the Newsnight interview to attack the role of the International Monetary Fund in Latin America, where it has a reputation for pushing market-based reforms as the price of its help to countries struggling with their finances.

The Chávez government has helped a number of countries, including buying Argentinian and Ecuadorean bonds, with Mr Chávez arguing that he would like to see the IMF replaced by an International Humanitarian Fund.

Backstory

Hugo Chávez was born in 1954. The former paratroop colonel first came to prominence after a failed coup in 1992, for which he was jailed for two years. He was elected president of Venezuela in 1998, launching a social programme known as Bolivarianism, after the revolutionary Simón Bolívar, and reversing planned privatisations. In 2002 he survived a coup attempt and, two years later, a bid to unseat him in a referendum. He has close links with Cuba's Fidel Castro and has frequently clashed with the United States.