The Bolivian president, Carlos Mesa, today claimed victory after exit polls showed voters had backed him in a referendum regarding the future of the country's vast natural gas reserves.

Early results also suggested the largely peaceful vote on Mr Mesa's five-question referendum had been a political success.

The outcome will grant the president a mandate to take more control over Bolivia's natural gas industry, raise taxes on foreign gas firms, and export gas. It should also avert a feared and predicted descent into civil unrest.

Natural gas is Bolivia's most profitable natural resource, with its gas fields valued at more than $70bn (£37bn). Around 20 foreign companies, including BP and British Gas, have invested $3.5bn in exploration.

However, the benefits created by foreign companies harvesting the gas have not been passed on to the majority of Bolivia's citizens. Statistics show that 80% of the country's 8 million citizens live in poverty, many of them members of its majority indigenous population.

In October, 60 people died during mass protests against plans to export gas through Chile. The unrest drove the former president Gonzalo Sanchez de Lozada from office, leaving Mr Mesa - who was then the vice-president - to restore calm.

His solution was to hold yesterday's referendum, with many seeing its success as a vote of confidence in him.

"Bolivia has shown the world today that it is not a country - as many had suggested - in risk of falling apart," Mr Mesa said yesterday. "The most important message is that peace has overcome violence."

Initial results from election officials were not expected until later today or tomorrow. Although highland indigenous leaders who helped lead the October revolts threatened to sabotage the vote, police had to deal with only minor violence in two highland spots between La Paz and Lake Titicaca. No injuries were reported.

Mr Mesa also said that voter turnout - a way of measuring the depth of his support - was "well over 50%".

It is likely to be weeks or months before it becomes clear how Bolivia's Congress can transform the referendum responses into laws that reflect the public will.

Political analysts said the referendum's questions had been so vague that interpreting them and enacting legislation would prove challenging for Mr Mesa, who has no formal political support in a Congress that is known for its internal squabbling.

"This is undoubtedly a victory for Mesa, but the government has only overcome its first obstacle. Now these referendum proposals must go to Congress, and that will be another battle. The difficulties may have just begun," Jorge Lazarte, a political analyst, said.

Some Bolivians remain wary of the referendum and pledges that exporting gas will increase incomes and social spending for the poor.

"There have been so many promises, and the government always does what it wants," Patricia Mamani, a 28-year-old street vendor in La Paz, said.

The gas reserves have pitted the wants of poor Indians in the western Andean plains against those of the business elite in the eastern and southern lowlands, where the gas is located. The business leaders are focused on exportation, and have threatened to secede from the republic.

The vote could also send a political signal across Latin America, where democratic leaders face voter backlash after a decade of market reforms that many argue have benefited only foreign firms and the rich.

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