RALEIGH, N.C. — Principals from every school in Wake County were invited Thursday to meet with other school administrators to discuss their school's emergency plans in case of a possible terrorist attack.

While administrators say there is no direct threat to North Carolina or Wake County, they want to be prepared.

As a precaution, Superintendent Bill McNeal canceled all field trips outside the United States.

"The safety of our students must be our main concern," McNeal said. "The restrictions may cause some students to be disappointed and result in some loss of deposits, but student safety is our first priority."

McNeal has asked school administrators to contact travel companies to make them aware of the school system's actions as schools cancel their trips. In March and April, band, chorus and orchestra groups from Wake County middle and high schools had planned trips to countries including the Bahamas, England, France, Guatemala and Spain.

Field trips and student travel may continue to locations in the United States, but McNeal noted that could change if federal and state agencies advise against it.

Other school systems are taking measures in response to a possible terrorist threat.

Cumberland and Johnston counties are following the state's lead. They said if they are told to, they will put into action their respective crisis plans.

Orange County leaders recently met to discuss their preparation. School principals are now reviewing procedures.

Chatham County schools routinely practice their emergency drill to make sure they are prepared, and Durham County schools are also ready to respond with their emergency plan.