Russia on Tuesday harshly criticized Europe's decision to allow the arming of Syrian rebels, saying it undercuts international efforts to negotiate an end to the civil war, and a rebel general said he's “very disappointed” weapons won't come fast enough to help opposition fighters defend a strategic Syrian town.

The European Union decision, coupled with a Russia's renewed pledge to supply Syrian President Bashar Assad's regime with advanced missiles, could transform an already brutal civil war into an East-West proxy fight. Israel, meanwhile, threatened to strike such air defense missiles systems if delivered to Syria, portraying them as a threat to the Jewish state and raising the risk of regional conflagration.

The possibility of an arms race in Syria overshadowed attempts by the U.S. and Russia to bring representatives of the Assad regime and Syria's political opposition to peace talks at an international conference in Geneva, possibly next month.

The talks, though seen as a long shot, constitute the international community's only plan for ending the conflict that began more than two years ago and has killed more than 70,000 people.

In Syria, the commander of the main Western-backed umbrella group of rebel brigades told The Associated Press he urgently needs Western anti-tank and anti-aircraft missiles to prevent further regime gains on the battlefield. The rebels' weapons are no match for the Syrian regime's modern tanks and warplanes, he said.

“We are very disappointed,” Gen. Salim Idris, military chief of the Free Syrian Army, said of the European Union's apparent decision not to send weapons, if at all, until after the Geneva conference. “We don't have any patience (any) more.”

In any case, Europe might think twice about sending such weapons into a chaotic war zone where they could quickly be seized by Islamic militant rebels, some of whom have pledged allegiance to the al-Qaida terror network.

Britain, which along with France had pushed for ending the EU arms embargo, wants to use the threat of arming the rebels as leverage to ensure that Assad negotiates in good faith.

Syria's fractured opposition, which has not yet committed to the Geneva talks, could also be lured to the table if attendance is linked to receiving weapons in the event that talks fail. Opposition leaders have said they will only participate in talks if Assad's departure from power tops the agenda, a demand Assad and his Russian backers have rejected.

British Foreign Secretary William Hague said peace talks are a priority and that “as we work for the Geneva conference, we are not taking any decision to send arms to anyone.”

However, Russian Foreign Minister Sergey Lavrov warned that recent actions by the West “willingly or unwillingly are undermining the idea of the conference.” He denounced the lifting of the EU arms embargo as an “illegitimate decision,” saying that supplying weapons to non-governmental groups “goes against all norms of international law.”

At the same time, Lavrov's deputy affirmed Tuesday that Russia won't abandon plans to send long-range S-300 air defense missile systems to Syria, despite strong Western and Israeli criticism. It is not clear if Russia has already sent some of the missiles, which would be a major boost for Syria's air defense capabilities, including against neighboring countries that oppose Assad's regime.

Russia's U.N. Ambassador Vitaly Churkin said that “to the extent those systems, if deployed in Syria, can deter foreign military intervention, I think it will help focus minds on a political settlement.”

Churkin, speaking to CNN, said Assad has assured Russia that a government delegation will attend the peace conference that Russia and the U.S. have called. The most difficult problem, he said, “is organizing the opposition.”

“We think that there is a chance with our concerted effort that the conference might start and might produce eventually results to end the conflict,” Churkin said.

U.S. State Department spokesman Patrick Ventrell said Washington welcomes the EU decision as a show of support for the Syrian opposition and as a message to the Assad regime that such support will only grow. He said the Obama administration will continue to provide non-lethal assistance to the rebels and hasn't made a decision on whether to arm them.

Ventrell condemned Moscow's decision not to drop plans to sell S-300 missiles to Syria. “We're talking about a regime that's willing to go to enormous lengths to use massive force against civilians, including Scud missiles and other types,” he said. “We condemn all support of arms to the regime.”

Further raising the risk of a regional war, Israel warned that it would be prepared to attack any such missile shipments. Israeli Defense Moshe Yaalon said Israel believes the Russian missiles have not yet been shipped, but that the Israeli military “will know what to do” if they are delivered.

Earlier this month, Israeli airstrikes hit suspected shipments of advanced Iranian missiles near the Syrian capital of Damascus that were purportedly intended for Assad ally Hezbollah, the Lebanese militia that is fighting alongside Syrian regime forces.

Israel has said it would not hesitate to attack again to disrupt the flow of game-changing weapons threatening its security.

France and Britain so far have not specified what weapons they might send. But the strategy of threatening to arm the rebels as a way of bolstering diplomacy could easily fail.

Assad's regime has provided no sign of any intent to cede power in Syria, a key opposition demand before entering any talks. Meanwhile, the opposition could try to make a public show of willingness to attend the talks, only to demand that weapons deliveries from Europe start right away if the hoped-for Geneva process breaks down.

The regime and the opposition are both still trying to win militarily. The two sides remain largely deadlocked, but in recent weeks the regime has scored a number of battlefield successes that might make it less inclined to negotiate.

Syria's Foreign Ministry said the EU decision exposes the “mockery” of European claims to be supporting a political solution to the crisis based on national dialogue, while “encouraging terrorists and extending them arms.”

On the other hand, Idris, the rebel commander, said his fighters could lose control of a strategic town in western Syrian in the coming days unless he gets weapons quickly.

He said thousands of Hezbollah fighters are participating in an offensive against Qusair that began May 19, and that his fighters are outnumbered by more than 3-to-1.

“Time is a very important factor now in the battle in Qusair,” he said. “When they wait for a week (to send weapons), maybe Qusair will be under the control of Hezbollah. Then we don't need their (the West's) help, we don't need their support.”

If Assad retakes the town, he would shore up his hold on the land corridor linking his stronghold in Damascus with loyalist areas along the Mediterranean coast. For the rebels, losing Qusair would mean losing a supply line to nearby Lebanon.

On Monday, Idris accompanied U.S. Sen. John McCain into a rebel-held area in northern Syria for a meeting with about a dozen local commanders. In a comment on Twitter, the Arizona Republican on Tuesday praised the “brave fighters” battling Assad and renewed his call for the Obama administration to move aggressively militarily to aid the opposition.

Michael Clarke, director of London's Royal United Services Institute think tank, said the EU decision will mean little on the ground for now. He said it is a message to Assad that “the Geneva process is the last good chance you're ever going to have of getting out of this situation without the civil war getting considerably worse _ and in one piece.”

He said it's also telling the Russians that “we are not going to be intimidated by a lot of Russian huffing and puffing at the moment.” (AP)