BEIRUT - The commander of the main Western-backed umbrella group of Syrian rebel brigades said Tuesday he is "very disappointed" that the lifting of Europe's arms embargo won't lead to immediate weapons shipments to his outgunned fighters.

Speaking by phone from Syria, Gen. Salim Idris also told The Associated Press that the Lebanese militia Hezbollah, an ally of the Syrian regime, has sent thousands of fighters to Syria and is emerging as the main threat to his Free Syrian Army, a coalition of rebel groups.

He called for urgent international action to stop the influx of Hezbollah fighters, warning that if no action is taken, FSA fighters might ignore his standing order and start targeting the Shiite militant group's bases in Lebanon.

The general spoke a day after the European Union decided to let its arms embargo against Syria expire, freeing member countries to provide weapons to the rebels. The push for lifting the arms embargo was led by Britain and France.

British Foreign Secretary William Hague said Tuesday that Britain could theoretically start arming rebels right away, but would not do so while U.S.-Russian efforts are under way to launch Syrian peace talks at an international conference in Geneva next month. Such talks appear to be a long shot since Syrian President Bashar Assad and the political opposition are at odds on their framework.

Asked Tuesday whether Britain and France had promised to start sending weapons now, Idris said: "Today, we heard that our British friends are not going to deliver weapons and ammunition."

"We are very disappointed," he said. "They lift the arms embargo and I don't know what they are waiting for."

"We don't have any patience (any) more," he added.

Idris said his fighters need anti-tank and anti-aircraft missiles to counter the superior fire power of Assad's regime. For now, the weapons the rebels have can't match up against Syrian warplanes and modern tanks, he said.

The West, particularly the United States, has been reluctant to send such weapons out of fear they might fall into the hands of Islamic extremists fighting in the rebel ranks, including members of Jabhat al-Nusra, which has sworn allegiance to al-Qaida.

Idris said he has repeatedly offered the West guarantees that the weapons would only be given to vetted rebel units, and that they would be returned if and when Assad is toppled. He denied that the extremists are dominant among the rebel fighters. Western-backed rebels have not explained how they would prevent Islamic militant or al-Qaida-linked fighters from seizing such weapons by force.

The general, a former lecturer at Syria's main military college, took up his post in December. He said he travels to rebel-held areas in Syria frequently, and also stays in touch with his officers by Skype.

Idris said Hezbollah has become the dominant fighting force in Syria with 15,000 fighters and that regime forces are fading into the background. His claim could not be independently confirmed. Hezbollah is a secretive organization and does not discuss the size of its military wing. However, the group is the dominant military force in Lebanon with an arsenal more powerful than that of the Lebanese army.

"Fighters of Hezbollah are coming very well organized, very well armed, and they are commanded by officers from ... the Revolutionary Guards in Iran," he said. "Russia is supporting the regime with technical information, with images from satellites."

Russia is a key ally of the regime, supplying arms and shielding Assad from international censure. Iran is another staunch ally, and has provided Assad with cash and weapons to help him try to stamp out the rebellion.

On Tuesday, Russia's deputy foreign minister, Sergei Ryabkov, said Russia reserves the right to provide Syria with state-of-the-art air defense missiles as a key deterrent against foreign intervention. Ryabkov wouldn't say whether Russia has shipped any of the long-range S-300 air defense missile systems, but added that Moscow isn't going to abandon the deal despite strong Western and Israeli criticism.

Idris said that unless the rebels receive weapons quickly, they might not be able to hold the strategic rebel-held town of Qusair in western Syria. He said thousands of Hezbollah fighters are participating in a regime offensive against Qusair that began May 19, and that his fighters are outnumbered by more than 3:1.

"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."

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

The general called for robust international action to prevent Hezbollah fighters from streaming into Syria, and suggested sending a U.N. force to the border between Syria and Lebanon as a buffer.

Idris said there's growing pressure from his men to let them attack Hezbollah bases in Lebanon. "If this kind of behavior of Hezbollah continues ... I can't control the units of the FSA anymore. They will start to target the bases of Hezbollah inside Lebanon's territory," he said.

The FSA is only one armed rebel organization in Syria. Dozens of brigades often make decisions locally, without coordinating or heeding a central command. Many fighters, particularly those belonging to Islamic extremist factions that are among the most powerful and effective of the rebel brigades, don't recognize Idris' authority.

The Qusair offensive has exposed Hezbollah's growing involvement in the Syrian civil war, with dozens of the militia's fighters killed in fighting there and buried in large funerals in Lebanon. Hezbollah chief Hassan Nasrallah has linked his group's fate to the survival of the Assad regime, confirming that Hezbollah is a party to the conflict.

Trying to court support for Western arms shipments, Idris on Monday accompanied Sen. John McCain on a surprise visit to a rebel-held area in Syria, near the Turkish border.

McCain, R-Ariz., a member of the Armed Services and Foreign Relations committees, favors providing arms to rebel forces in Syria and creation of a no-fly zone. He has stopped short of backing U.S. ground troops in Syria.

Idris said McCain spent about two hours in Syria, meeting with 10-15 local commanders. His discussions focused on the fighting on the ground, the need for military assistance, humanitarian aid and medical care, Idris said.