South America edged closer to a regional war yesterday as troops from two nations massed on Colombia’s frontiers, and the country, a key US ally, was accused of becoming “the Israel of Latin America”.

The region was locked in a tense military stand-off after Venezuela and Ecuador sent thousands of troops, backed by tanks and fighter jets, to their borders with Colombia.

Hugo Chávez, the Venezuelan President, yesterday denounced Colombia over the killing of a top Marxist guerrilla just inside Ecuadorean territory on Saturday and said: “This could be the start of a war in South America.” He warned his Colombian counterpart: “If you think of doing this in Venezuela, we are going to send you some Sukhoi” — fighter jets he bought recently from Russia.

Colombia responded by producing evidence purporting to link Mr Chávez financially with the Farc rebel group, who they sensationally claimed last night had also been dealing in uranium.

Fidel Castro, who stepped down as Cuban leader last month, blamed the US for the rising temperature. “We can plainly hear the trumpets of war to the south of our continent as a consequence of genocidal plans of the Yankee empire,” he wrote in Granma, the Communist Party daily. Mr Castro counts himself as a close friend of the Venezuelan President, who provides up to $2 billion a year in aid for Cuba.

The US, which has backed Colombia in its decades-long fight against the Marxist guerrillas, said it was monitoring the situation closely. “This is an odd reaction by Venezuela to Colombia’s efforts against the Farc, a terrorist organisation that continues to hold Colombians, Americans and others hostage,” Gordon Johndroe, the White House spokesman, said.

Ecuador, ruled by Rafael Correa, an ally of President Chávez, initially reacted calmly to news of Colombia’s military operation, which claimed the lives of the top Farc commander Raúl Reyes and at least 20 other rebel fighters. He stepped up his rhetoric sharply, however, after consultations with Mr Chávez, who called Álvaro Uribe, the Colombian President, a criminal and a puppet of the US Government.

Ecuador and Venezuela severed diplomatic contact with Colombia yesterday, expelling the Colombian Ambassadors in Quito and Caracas.

Colombia said that its soldiers had acted in self-defence after being fired upon by the rebels just inside Ecuadorean territory. But Mr Correa said the operation that killed Reyes was a massacre, not a hot pursuit. Some of the dead rebels were found in their pyjamas and killed while they slept, he claimed. “Colombian planes came at least 10km inside our territory during their attack,” he said. “They are lying to Ecuador and to the world.”

Colombia hit back yesterday, accusing the Ecuadorean Government of forging links with the Farc rebels. It then heightened tensions further last night by claiming that documents recovered from a laptop computer belonging to Reyes suggested direct financial ties between Mr Chávez and guerrillas. They also suggested that the rebels had entered the big leagues of global terrorism by buying and selling Uranium.

Oscar Naranjo, Colombia’s police chief, said that one message mentioned $300 million in apparent support for the rebels. He did not say whether Venezuela delivered the money.

Another document on the laptop also suggested financial ties between Mr Chávez and the rebels dating back to 1992, Mr Naranjo said. At the time, Mr Chávez was in jail in Venezuela for leading a coup attempt and was plotting the comeback that eventually led to his election as President in 1998.

“A note recovered from Raúl Reyes speaks of how grateful Chávez was for the 100 million pesos [about £75,000] that the Revolutionary Armed Forces of Colombia, or Farc, delivered to Chávez when he was in prison,” Mr Naranjo said.

All three countries sought international backing yesterday, as countries including Spain, Brazil and France worked to defuse the crisis. Despite the rising tension some analysts believe that Mr Chávez — who recently suffered his first electoral defeat in nine years — is using the incident as a distraction from problems at home and to rally wavering supporters.

“Chávez is facing an extremely difficult situation,” said Carlos Malamud, a Latin America analyst at the Madrid-based Royal Elcano Institute. “His popularity has dropped considerably and his greatest concern is the lack of basic products on the shelves. So he wants to try to rally Venezuelans behind nationalist and anti-imperialist slogans.”

However, analysts worry that a misstep could spark fighting. Mr Malamud said: “Someone on either side could make a mistake that ends up blowing up into conflict.”

Relations between the two neighbours have been poisoned since Colombia’s conservative President ended an effort by Mr Chávez to negotiate an exchange of about 40 political hostages held by the Farc for hundreds of guerrillas in Colombian jails.

Venezuela

Defence budget (2007): $2.56 billion

Active members of military: 115,000

Reserve members of military: 8,000

Main battle tanks: 81

Light tanks: 109

Armoured personnel carriers: 71

Attack helicopters: 13

Planes (combat capable): 104

Submarines: 2

Warships (principal surface combatants): 6

Colombia

Defence budget (2007): $5.10 billion

Active members of military: 254, 259

Reserve: 61,900

Armoured personnel carriers: 228 plus

Attack helicopters: 31

Planes (combat capable): 115

Submarines: 4

Warships (principal surface combatants): 4

Ecuador

Defence budget (2007): $918 million

Active members of military: 57,100

Reserve members of military: 118,000

Light tanks: 24

Armoured personnel carriers: 123

Attack helicopters: 18

Planes (combat capable): 57

Submarines: 2

Warships (principal surface combatants): 8

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