The Knesset yesterday voted to advance an amendment that would require a referendum on any withdrawal from sovereign Israeli territory, such as the Golan Heights.

The vote comes in the wake of Prime Minister Benjamin Netanyahu's announcement Monday that Syria is now willing to negotiate peace with Israel without any preconditions, reportedly agreeing to drop its demand of a complete Israeli withdrawal from the Golan.

Opposition members accused Netanyahu of supporting the amendment as a ploy to "tie his own hands," preventing him from signing any peace agreements.

The motion passed by a large majority, including approval from Defense Minister and Labor chairman Ehud Barak who said he objected to the bill in principle, and Deputy Prime Minister Dan Meridor, who had recently appealed against it.

Barak voted in favor of the motion despite the stance taken by most Labor faction members and despite his own opinion, drawing fire from Laborites.

"It's absurd to make a move that changes the system of government in an off-handed way without a comprehensive debate," MK Isaac Herzog (Labor), who storm out of the plenum hall before the vote, said. "It could prove to be a redundant, reckless move."

Labor MKs Benjamin Ben-Eliezer and Matan Vilnai joined Barak in supporting the amendment, while Shalom Simhon, Avishay Braverman and Orit Noked were all absent.

Labor MKs Shelly Yachimovich and Daniel Ben Simon joined the faction's four rebels in opposing the proposal.

While existing law technically demands a referendum on any withdrawal from territory under Israeli sovereignty, it also rendered this requirement inoperative until legislation was passed to regulate how a referendum would take place. MK Yariv Levin (Likud), who chaired the committee that authored the current amendment, said the new legislation governs how a referendum would be held, what kind of questions would be posed, how any publicity would be managed and how the vote itself would be conducted.

The amendment was initially approved in a first reading by the previous Knesset. Under house rules, however, the current Knesset is required to reaffirm this vote in order for the bill to continue advancing.

Earlier Barak claimed that the Labor party objects to the suggested amendment, but if the vote turns into a no-confidence motion, as the Meretz party suggested, Labor ministers would be forced to vote in favor of the bill.

"The referendum proposal is unnecessary," said Barak. "First, the law imposes unnecessary restrictions on the prime minister in his negotiations with Syria, and could create a false impression in the world that Israel is opposed to peace."

"Second," he continued, "a referendum is a complex matter, and in many ways contradicts the principle at the base of parliamentary government."

The bill was scheduled to be voted on about a month ago, but Meridor appealed the ministerial committee's decision to support it, and the vote was delayed. On Tuesday, the committee dismissed Meridor's appeal, clearing the path for yesterday's vote.

Opposition leader Tzipi Livni (Kadima) voted against the bill, which she said would restrict the government's ability to advance peace. Kadima MKs Meir Sheetrit and Nachman Shai joined her, while MKs Ruhama Avraham Balila, Yoel Hasson and Yisrael Hasson supported it.