(Telegraph)

Tensions between the countries reached a new high after the Colombian military arrested four Venezuelan soldiers, just days after Mr Chavez told his army to “prepare for war” with Colombia.

The Venezuelan ambassador to Bogota, Gustavo Marquez, said that the seriousness of the situation could not be overstated and that “there is a pre-war situation in the entire region”.

Diplomatic relations between the South American neighbours are frozen and on Saturday President Chavez escalated the war of words with President Alvaro Uribe of Colombia by saying there was no chance of dialogue.

“Uribe is not a politician, he comes from the world of paramilitaries, of drug trafficking, of shady business deals, and he is capable of anything,” the Venezuelan leader said.

“He is a very dangerous man as he has no principles or ethics,” Mr Chavez added.

The broadside came after Colombia detained four members of the Venezuelan National Guard in a boat allegedly on Colombian territory in the remote border province of Vichada. Colombia said yesterday that it would deport the men back to Venezuela.

Tensions between Presidents Uribe and Chavez have escalated in recent months as the two leaders have become increasingly suspicious of each other.

Colombia’s Marxist rebels, the Guerrillas of the Revolutionary Armed Forces of Colombia (FARC) and the smaller National Liberation Army (ELN), are known to have bases within Venezuela from where they plan and launch attacks on Colombia’s US-backed army.

Mr Chavez hotly denies any links with the rebels, even though there have been seizures of Venezuelan arms and munitions in FARC camps.

Venezuela’s president is angry at an agreement signed earlier this month between Bogota and Washington under which Colombia allows the US military to use seven bases across the country, turning the Andean nation into America’s regional military hub.

Mr Chavez, who accused Washington of being behind a 2002 coup attempt, insists that the US is planning to attack Venezuela to secure control of massive oil reserves. The Venezuela leader believes that Colombia will now be the launch pad for any US attack.

President Uribe is trying to diffuse tensions since Mr Chavez began blocking the entry of Colombian goods, something which is costing the fragile economy hundreds of millions of pounds.

He stated that the captured Venezuelan soldiers would be returned as quickly as possible and “carry with them the message that here their affection for our Venezuelan brothers and that this affection is unquenchable”.

Mr Chavez has ordered another 15,000 soldiers to take up positions along the 1300-mile frontier, while Colombia has created a new division of its army to guard a strategic stretch of the border.

Analysts worry that Marxist rebel groups could manipulate the troop build-up by starting a firefight, sparking a war between the two countries.