Federal agencies will be closed Friday as part of the national day of mourning for former president Ronald Reagan, the White House announced last night. In an executive order, President Bush said federal government offices "shall be closed on June 11, 2004, as a mark of respect for Ronald Reagan." Federal offices and programs essential for national defense, homeland security, foreign affairs, law enforcement and other essential business may be kept open, however, at the discretion of agency heads, the order said. Administration officials said additional information would be sent to agencies today on the closing of the government for the Reagan funeral on Friday.