Argentina's takeover of its top energy company from Spain's Repsol, in an effort to control its energy future, has provoked an avalanche of diplomatic protests and vows of retaliation from Spain and other affected parties like Mexico.

President Cristina Fernández de Kirchner has made Spain furious by decreeing that her government will recover YPF SA, Repsol's Argentine oil operations, by expropriating Repsol's majority stake in the company. 

President Fernández said the company hasn't invested enough in the South American country and has rejected Repsol YPF's demand for $10.5 billion in compensation. Argentina is still in the process of valuing its' 51 percent of YPF's shares and will not use estimates from Repsol, the Deputy Economy Minister Axel Kicillof said at a Senate hearing yesterday.

Shares of Spanish energy company Repsol plunged Tuesday after Argentina announced plans to nationalize YPF.

While the takeover might solve the country's short-term energy needs, and it thrills Argentines who blame privatizations for their economy's collapse a decade ago, some analysts say it sends a terrible signal to anyone wanting to invest in Argentina.

This creates an uncertainty which is not helpful to our economic relations and to the economy as a whole.

- José Manuel Barroso, President of European Commission

Fernández, who already nationalized Argentina's flagship airline and private pension funds, said her aim is nothing less than to recover her country's sovereignty. She accused Repsol of provoking an energy crisis by exporting too much of Argentina's oil and failing to invest locally even as it paid huge dividends abroad.

Re-nationalizing YPF is a gamble that could boost her popularity ratings, which dropped from 70 percent in January to 50 percent in April, according to the Poliarquia tracking poll, following a scandal involving her vice president, soaring inflation, a cooling economy, reductions in utility and transportation subsidies and a deadly train crash.

Crowds turned out Tuesday to cheer the move, including a group that briefly invaded a YPF plant in La Plata and replaced a Repsol flag with Argentina's. Then they stomped on the Spanish banner and drove a car over it for good measure.

However it also could scare off investors just when YPF needs billions of dollars and long-term commitments to exploit what could be the world's third largest unconventional energy reserves, in Argentina's Patagonia region.

"It sends off a terrible image of Argentina because the country is once again violating property rights as it did during the debt default or the nationalization of the Anses state pensions fund," said Sergio Berensztein, who runs Poliarquia, a Buenos Aires consulting firm.

"Argentina's reputation is going to suffer a lot and many investments will be lost," Berensztein predicted. "I don't think Argentina has a socialist ideology like Chavez's Venezuela but it is evidently becoming more radicalized and in both cases the state will continue to intervene in companies."

The takeover comes after months of pressure on YPF to increase its Argentine oil and gas production. Provincial governments have rescinded YPF licenses in major oil fields, alleging the company broke its contracts by failing to invest more. Repsol denies this, saying it has invested billions in the fields over the years, and planned to ramp up production even more.

Fernández named Planning Minister Julio de Vido and Deputy Economy Minister Axel Kicillof to run the company, which had been state-owned since the 1920s and a source of pride for Argentines until it was privatized in the 1990s.

At a heated senate hearing to discuss the bill on Tuesday, De Vido asserted that many energy companies had expressed interest in the last few hours in replacing Repsol. He said the intervention would be short, and would turn YPF into a stronger, forward-looking company, not one that is "silly, foolish and autistic."

Energy-rich Argentina has gone from being a major exporter of natural gas and oil to a major buyer of expensive energy imports that erode its trade surplus, which has helped sustain Argentina's high economic growth over the past nine years.

Repsol President Antonio Brufau dismissed the criticism and accused Fernández of trying to cover up Argentina's economic and social ills with the "unlawful" expropriation, which caused the group's shares to plunge more than 7 percent on Tuesday. He said the company aims for compensation of at least $10.5 billion.

Kicillof cast doubt on that figure, saying YPF has major debts to pay and suggesting that environmental cleanup costs also will be deducted from whatever his government pays.

"We're going to see where they threw out each cubic meter of contaminated water," Kicillof vowed.

Kicillof also accused Repsol of hiding the true value of its Argentine unit, and said a thorough review of its books after seizing control of its offices in Buenos Aires will affect the compensation paid to its shareholders.

The measure is likely to win swift approval in Argentina's congress, where Fernández counts on a majority in both houses. But analysts say the government lacks the resources to pay what Repsol is demanding while also maintaining a populist spending spree. The state may turn to central bank reserves or state pension funds to pay off Repsol, but will likely need deep-pocketed partners to exploit its shale reserves.

The move spoils Argentina and Spain's good relations and "greatly affects the international reputation of Argentina," Spanish Prime Minister Mariano Rajoy said at a World Economic Forum meeting in Puerto Vallarta, Mexico.

Argentina's move also affects Mexico's state-owned Petroleos Mexicanos, which owns 10 percent of Repsol and is among many shareholders around the world who watched the announcement with dismay.

"I am absolutely convinced that the road to economic growth and development is not the road of expropriations," said Mexican President Felipe Calderon, though his country each year celebrates the 1938 nationalization of its own oil industry.

Spain's government prepared retaliatory measures, the European Commission indefinitely postponed a bilateral trade meeting between the European Union and Argentina, and other countries were considering diplomatic, legal and economic counter-measures.

"This creates an uncertainty which is not helpful to our economic relations and to the economy as a whole," European Commission President José Manuel Barroso said.

Repsol shares closed down 6 percent to €16.42 ($21.43) in Madrid, far underperforming the benchmark Ibex index. Analysts were concerned that Argentina has not stated any compensation terms for the nationalization of YPF, which has 42 percent of Repsol's global reserves, estimated at 2.1 billion barrels of crude.

Spain's government is lining up allies to contest the nationalization and possibly isolate Argentina economically. Rajoy was already finding support during his trip to Mexico. Venezuela, meanwhile, pledged to use all means necessary to support Argentina.

Based on reporting by the Associated Press.

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