Six candidates under the Democratic Unity coalition banner are vying in a February 12 primary to become the lone opposition candidate to take on the incumbent Chavez, whose state-led economic model they oppose.

Current favorites in the polls, governors Henrique Capriles and Pablo Perez, signed the document as did lawmaker Maria Corina Machado, former mayor Leopoldo Lopez and union organizer Pablo Medina all signed on. Ex-ambassador Diego Arria was the only candidate not to sign it.

Among the changes opposition members sought were dropping price controls in place since 2003, adopting a competitive exchange rate, reassessing Chavez' creation of a socialist State, and returning autonomy to the Central Bank.

A staunch critic of the United States, Chavez is the key political and economic ally of Cuba, the Americas' only one-party communist regime. He also has launched economic support programs for sympathetic governments across Latin America.

Chavez is seeking a third six-year term in the October 7 vote.