Venezuela and Ecuador reinforced their borders with Colombia yesterday as the three countries traded increasingly bitter accusations over Colombia’s cross-border strike on a leftist guerrilla base in Ecuador.

Ecuador rejected a Colombian apology as insufficient and sought international condemnation of the attack during an emergency meeting in Washington of the Organisation of American States.

President Correa of Ecuador called his Colombian counterpart, Álvaro Uribe, a “bold-faced liar”. President Uribe demanded that the International Criminal Court try President Chávez of Venezuela for genocide.

America weighed in, with President Bush accusing Mr Chávez of “provocative manoeuvres” and declaring US support for Colombia.

The crisis, Latin America’s gravest for decades, erupted when Colombia sent troops into Ecuador on a raid last Saturday that killed 23 guerrillas, including the rebel spokesman Raúl Reyes, who was engaged in hostage talks with Venezuela, France and other countries.

Mr Uribe said that Mr Chávez should be prosecuted for allegedly financing the Revolutionary Armed Forces of Colombia (Farc). The Colombian President cited documents found on a laptop seized in Reyes’s jungle camp which he said showed that Venezuela recently made a $300 million (£150 million) payment to the rebels. Other documents indicate that the rebels were trying to buy uranium to resell at a profit.

Both Venezuela and Ecuador dismissed the allegations as lies.

Mr Uribe said that he would not allow his country to be drawn into open war. His more than 250,000 US-equipped, trained and advised soldiers, however, would outnumber the 172,000 active troops Venezuela and Ecuador have between them. “Colombia has never been a country to go to war with its neighbours,” Mr Uribe said. “We are not mobilising troops, nor advancing toward war.”

Venezuela was sending about 9,000 soldiers – ten battalions – to the border region as “a preventive measure”, according to retired General Alberto Müller Rojas, a former top Chávez aide. Ecuador said that it sent 3,200 troops to the border on Monday.

Saturday’s raid by Colombian troops is unlikely to lead to war, but it is a huge setback to peace and hopes for the release of hundreds of hostages held by left-wing rebels.

Details remain sketchy, but the raid appears to have targeted Reyes, 59, one of the top three leaders of Farc, Colombia’s main left-wing guerrilla army that has waged war against the state for four decades.

The raid highlights potentially explosive tensions between Colombia and its neighbours over Farc’s use of porous borders to smuggle cocaine in return for weapons, as well as using foreign soil for “rest and recuperation” camps.

Mr Chávez has openly expressed his sympathy with Farc, recently calling on the rest of the world to recognise the group’s legitimate belligerant status. Farc is officially labelled as a terrorist group in Europe and the US, making it illegal for supporters to raise funds or otherwise provide aid for it.

Reyes was also one of the most familiar faces of Farc, acting as its chief spokesman and peace negotiator, so it was not unusual for him to have contact with foreign governments. His death comes on top of a series of military setbacks in recent years for Farc, which has been forced to retreat into more remote, rural areas while its ranks have shrunk to about 10,000 because of combat deaths and desertions.

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