An asteroid up to a half a mile wide and with the power to wipe out a small country will miss the Earth Monday, according to media reports.

Asteroid 2004 XP14, discovered in December 2004, is one of a class of "Apollo" asteroids, whose orbits cross that of the Earth.

The body has been classified as a potentially hazardous asteroid (PHA) along with 782 known others.

Initial speculation by scientists predicted the possibility of impact with Earth later this century, but that conclusion has been ruled out, the Sunday Telegraph reported.

If XP14 did hit the Earth the effects would be devastating. "It would probably be big enough to wipe out a small country," said Dr David Asher, from the Armagh Observatory in Northern Ireland.

The asteroid is expected to make its closest approach to the Earth at 268,624 miles away, or 1.1 times the moon's average distance from Earth - a near miss in astronomical terms.

It is not big enough to see with the naked eye, but may be spotted by seasoned observers with moderate-sized telescopes.

(Xinhua News Agency July 3, 2006)