At a packed gymnasium in the Bolivian city of El Alto, Chavez repeated accusations that the US was trying to assassinate him and close ally Evo Morales, Bolivia's president.

"The Empire is in counterattack, with the head of the empire himself leading the attack,'' Chavez said.And why? Because they realise that the popular Latin American offensive is for real," he said.

Chavez said Latin America must fight back. "We have resisted for a long time. But no one wins a battle always staying on the defensive," he said.

He alleged that the US embassies in Venezuela and Bolivia were plotting to overthrow him and Morales, citing the US-backed 1973 coup in Chile that toppled socialist president Salvador Allende as a precedent.

Chavez, left, accused the US of plotting to kill him and Evo Morales, Bolivia's president [AFP]

After signing several agreements with Bolivia to strengthen ties with Venezuela, he moved on to Nicaragua late Sunday, meeting Daniel Ortega, Nicaragua's president.

Chavez is due to travel to Jamaica as well as Haiti on Monday.

Bush in Colombia

Bush was in Colombia's capital, Bogota, for a six-hour visit as part of his five-nation Latin American tour.

Nearby, at least 25 people were arrested as riot police using tear gas clashed with demonstrators protesting against Mr Bush's visit.

Mr Bush praised Mr Uribe's efforts to tackle the country's trade in illegal drugs, much of it destined for the US.

"I appreciate your determination, and I'm proud to call you a personal friend, and to call your country a strategic partner of the United States," Mr Bush told his Colombian counterpart during a news conference.

Bush, right, reiterated ties between Washington and Bogota [AFP]

The visit is overshadowed by a scandal about alleged links between Mr Uribe's allies and right-wing paramilitaries.

Colombia is one of the largest recipients of US aid to help fight a long-running war against left-wing guerrillas and drug traffickers.

Some US Democrats are questioning a White House request for $3.9bn in new aid over the next seven years as well as the wisdom of a US trade deal with Colombia.

Since 2000, Colombia has received billions of dollars of US funds and military hardware.

Colombia was the third country on the president's five-nation tour of Latin America; he visits Guatemala and Mexico before returning to Washington on Wednesday.

Agencies