Hugo Chávez, Venezuela's president, will on Tuesday host a summit with the leaders of Brazil, Colombia and Spain an occasion that will allow Caracas to court foreign allies and offset deteriorating relations with the US.

The summit in the Venezuelan city of Puerto Ordaz comes amid US worries over Venezuela's plans to buy a range of military weapons. Mr Chávez, leader of the world's fifth-largest oil exporter, says the arms will shore up national defences.