BRASILIA, May 23 (Xinhua) -- Colombia will not join a proposed regional defense council in South America due to "the terrorist threat" it faces at home, a presidential spokesman said here Friday.

    Colombia "cannot take part in the South American Defense Council due to the threats of terrorism," Cesar Mauricio Velazquez, a spokesman for Colombian President Alvaro Uribe, said during a regional meeting at which 12 countries signed a treaty to create the Union of South American Nations (Unasur).

    In a statement, Velazquez also said his country "does not oppose the creation of a working group to study the theme."

    Earlier this week, Uribe announced his refusal to approve the proposal, made by Brazil, saying the Colombian government is experiencing a difficult time in its fight against the Revolutionary Armed Forces of Colombia, the largest rebel group in the country.

    Such a regional defense body would not offer solutions to Colombia's problem, he said.

    After Colombia's rejection of the defense council, the other 11Unasur members -- Argentina, Bolivia, Brazil, Chile, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay and Venezuela -- agreed to establish a task force to present a revised proposal within three months.