US ties denounced

Chavez told an audience of environmental activisits that an agreement between the Dutch and the US permits Washington to keep 250 airforce crew and ground staff just 24km off the Venezuelan coast.

"I am accusing the Kingdom of the Netherlands, along with the Yankee empire [the United States], of preparing aggression against Venezuela", the president said in remarks broadcast by Venezuelan state television.

US air crews are officially involved in counter-narcotics and surveillance operations, and operations are undertaken from the air by unarmed planes only, the Dutch foreign ministry spokesman said.

Chavez also pointed to the reactivation of the US Navy's Fourth Fleet, which had been disbanded in 1950 but began to patrol the coast of South America earlier this year, as further evidence of a conspiracy to surround his country.

The Venezuelan president's remarks come as political tensions with neighbouring Colombia escalate.

Colombia has agreed to give Washington more access to its military bases, a move Chavez says is designed to threaten his eastern border.