A South American trading bloc that includes Brazil, Argentina and Uruguay agreed Tuesday to close its ports to ships flying the flag of the disputed Falkland Islands, Uruguay's president said. The presidents of the Mercosur countries agreed at a summit here that ships flying the Falklands flag "should not dock in Mercosur ports, and if that were to happen, they should not be accepted in another Mercosur port," Uruguay's President Jose Mujica said.