Thailand's military said it is ready to launch a "high-level operation" to counter any violation of its sovereignty, in the strongest words yet in a simmering border dispute with Cambodia that re-erupted with a deadly clash last week.

Tension has been rising between Thailand and Cambodia following the killing of a Cambodian soldier on May 28 during a brief exchange of gunfire at a disputed border area between the two Southeast Asian neighbours.

Thailand’s armed forces are ready to defend the border in the face of a deadly clash with Cambodia that erupted last week, a top official said, adding that the country wants to maintain peace with its neighbor.