OCCUPIED JERUSALEM: Israel has lodged a complaint with the U.N. after Syrian soldiers crossed last week into the demilitarized Golan Heights zone that separates the two countries, a foreign ministry spokesman said Sunday.

"Israel has formally complained to the U.N. as this is a serious incident. (This complaint) constitutes a very clear message that we address via the U.N. to those who control Syria," said Lior Ben Dor.

In a letter addressed to U.N. Secretary General Ban Ki-moon and to the U.N. Security Council, Israel's deputy ambassador to the U.N. Haim Waxman said Syria had violated a peace agreement by infiltrating the zone.

"On July 19 in the midst of fighting between Syrian security forces and other armed elements near the Syrian village of Jubata al-Khashab, Syrian soldiers crossed into the area of separation under the 1974 Separation of Forces between Israel and Syria" accord, Waxman said.

This was a "blunt violation of this agreement," he said, "with potentially far-reaching implications for the security and stability of the region."

"The Security Council should address this alarming development with great seriousness," he said, adding that the incident took place the same day as an inspection of the Golan Heights by Israeli Defense Minister Ehud Barak.

Israeli daily newspaper Haaretz reported that 500 Syrian soldiers and 50 vehicles had crossed into the zone.

Syria remains formally at war with Israel, which captured part of the Golan Heights in the 1967 Middle East war and annexed it in 1981 in a move which the international community does not recognize.

The Golan Heights is controlled by U.N. peacekeeping troops.