Venezuela is threatening to sever diplomatic ties with Colombia in protest at plans to allow the US to boost its military presence in the country. Colombia and the US are currently negotiating a deal to allow US soldiers to be stationed at seven Colombian military bases. The US claims the move is designed to boost the fight against drug trafficking and terrorism. Venezuela, however, says the move is designed to intimidate President Hugo Chavez. Mr Chavez, an outspoken critic of the US, has been trying to establish a "Bolivarian alternative" to the US-style free-market economic model in Latin America. He says the new US-Colombia deal is a threat to Venezuela and he has told his foreign minister to "begin preparing for the rupture with Colombia".