Drills aimed at warning Yugoslavs about Kosovo

WASHINGTON (CNN) -- NATO warplanes are to begin mock air attacks in the skies over Albania and Macedonia on Monday, CNN has learned.

About 30 warplanes from the United States, Britain, Canada, Italy and France will participate in the exercise, the sources said. There are no plans to drop live bombs, and the demonstration may amount to little more than "flyovers" by the planes, they said.

Although current plans are to begin the exercises Monday, delays in staging still could occur as NATO's leadership works to iron out details, according to NATO sources who asked not to be identified.

On Thursday, NATO defense ministers announced the military exercises, in response to the military crackdown by Yugoslav forces on ethnic Albanian separatists in the Yugoslav province of Kosovo.

Albania and Macedonia -- which border Kosovo on the south but are not NATO members -- have given permission for the NATO exercises.

The display of air power is designed to demonstrate to the Yugoslavs that NATO is seriously considering the use of military force to stop the crackdown in Kosovo, if the Yugoslavs don't end it on their own.

In the event that the air exercise doesn't sufficiently make the point, the NATO ministers also directed their staffs to begin planning for possible military intervention, including air strikes on military targets in the Yugoslav federation and possibly even the use of ground troops.

In preparation for the mock air raids, two U.S. Navy ships, the USS Wasp and the USS Portland, were called back one day early from a port call in Antalya, Italy, so they could be available to perform search-and-rescue missions if any NATO aircraft crash.

The United States has a substantial amount of air power in the region, including 36 F-16 fighters at an air base in Aviano, Italy. Some of those planes are outfitted to fire missiles that seek and destroy hostile radar sites.