UNITED NATIONS (AP) -- U.N. Secretary-General Ban Ki-moon warned that spillover from Syria's civil war threatens a 40-year-old cease-fire between Syria and Israel in the disputed Golan Heights and recommended bolstering the vulnerable U.N. peacekeeping force there by more than 300 troops.
Ban's recommendation, made in a report to the Security Council on Wednesday, came even as the U.N. seeks replacements for Austrian peacekeepers who are withdrawing from the Golan Heights after fighting threatened their positions.
"The ongoing military activities in the area of separation continue to have the potential to escalate tensions between Israel and the Syrian Arab Republic and to jeopardize the ceasefire between the two countries," Ban said.
Ban called for strengthening the 911-member peacekeeping force to 1,250 and improving its self-defense equipment. He recommended the Security Council extend the mandate for another six months, until December. The force, known as UNDOF, has been posted in the Golan since 1974 to monitor the cease-fire.
In a heavy blow the mission, Austria announced last week announced it would pull out its 377 peacekeepers. The Austrian peacekeepers left their posts and began withdrawing from the Golan Heights on Wednesday. Associated Press footage showed Austrian troops leaving the Syrian side and moving to the Israeli side of the Golan on at the Quneitra crossing point, which was briefly overrun by Syrian rebels last Thursday.
Austria's Defense Ministry spokesman Col. Michael Bauer said between 60 and 80 soldiers from the Golan were expected to land later in the day at Vienna airport.
Ban said he regretted Austria's withdrawal and that "efforts are underway to identify urgently additional contributions and new contributors to UNDOF."
A Security Council diplomat said Fiji has offered to send troops and that Ban has been lobbying the Philippines to send additional peacekeepers. The diplomat, who spoke on condition of anonymity because the discussions are confidential, said Philippine government is considering the request.
The peacekeeping force already includes 341 Philippine soldiers, one of whom was wounded last Thursday in fighting between Syrian rebels and government troops.
The Syrian rebels overran a U.N. position at the border post near the abandoned town of Quneitra last Thursday, holding it for several hours before Syrian government troops retook it. The peacekeepers receive most of their supplies through that position from Israel.
Fierce Syrian gunbattles forced the peacekeepers to seek shelter in a nearby base. U.N. diplomats said an Indian peacekeeper also was injured that day.
Israel's Prime Minister Benjamin Netanyahu said this week that the Austrian withdrawal shows his country can only rely on itself for security.
Israel has been warily watching the Syrian conflict since it broke out in March 2011, fearing the violence could spill across its borders at any time.
And although Syrian President Bashar Assad is a bitter enemy, Israel has been careful not to take sides in the war next door, partly because the Assad family has kept the border with Israel quiet for the past 40 years.
Israel is also concerned that if Assad's regime is toppled, Syria could fall into the hands of Islamic extremists, some of whom are linked to al-Qaida, fighting against the Syrian regime.
Israel and Syria agreed to creation of the U.N. Disengagement Observer Force after the 1973 Mideast war.
Associated Press writer Ian Deitch in Jerusalem and George Jahn in Vienna contributed to this report.
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