JERUSALEM (USA TODAY) -- Israel warned Thursday that it needed to prepare for a "new era" of war in the Middle East as the Syrian regime claimed the first shipment of anti-aircraft missiles from Russia had arrived.
The message comes as the Syrian opposition announced it will not attend a peace conference pushed by the Obama administration, crushing hopes of a ceasefire agreement soon in a war that is rapidly spilling across borders.
Israel vowed to target the S-300 long-range missiles that Russia has promised to send to Syria, insisting the rockets are an offensive weapon that could target Israeli commercial aircraft as well as its fighter jets inside Israeli airspace.
Speaking at the conclusion of a five-day civil defense drill that simulated missile attacks from Syria, Israel Prime Minister Benjamin Netanyahu said Israel "must prepare defensively and offensively for the new era of warfare."
"The Israeli home front is more accessible to the enemy than it has been," he said.
His remarks come as fighting between the rebels and Syrian military continued Thursday in the town of Qusair near the border with Lebanon. The Syrian army Wednesday took control of nearby Dabaa air base with the help of hundreds of Hezbollah militants.
The region is important to rebels who use it to transport supplies to their fighters. If lost would be a significant setback for the opposition, which has controlled the region for a year.
Syrian dictator President Bashar Assad told Lebanese network Al Manar, the voice of U.S.-designated Islamic terror group Hezbollah, that he is in possession of the first shipment of the Russian missiles and will receive the rest "soon." The interview was reported by Lebanese newspaper al-Akhbar.
Assad also warned Israel to stay away from the missiles, which would make it more difficult for Israel to strike targets inside Syria. Israel Defense Forces have launched airstrikes against convoys of weapons headed for southern Lebanon, the base of arch enemy Hezbollah that is on Israel's northern border.
Syrian Foreign Minister Walid al-Moallem told Lebanon's Al-Mayadeen TV that Damascus "will retaliate immediately" if Israel strikes Syria again.
Russia had earlier refused pleas from Israel and the United States to hold off on the delivery of the missiles. Russia has been supplying Assad with heavy weaponry and opposing proposals by the West to help the rebels topple Assad, whose forces have killed at least 80,000 civilians according to the United Nations. Russia says the missiles would help "stabilize" the regional balance.
White House spokesman Jay Carney said that Russia's arming the Syrian regime "does not bring the country closer to the desired political transition."
Israel Defense Minister Moshe Ya'alon said this week that if the missiles are delivered, Israel will "know what to do."
The S-300s can hit aircraft and guided missiles. Israel says the missiles could also reach deep into its territory, possibly hitting flights over Tel Aviv.
Shaul Shay, a senior research fellow at the BESA Institute at Bar Ilan University, said he isn't convinced that the missiles are already in Syria. But he didn't downplay the threat to Israel and others.
"You have to take into consideration that this is one of the most advanced anti-aircraft systems, despite Russian claims that it is a defensive system."It can be a threat to the capability of the Israeli air force to operate."
Equally frightening, Shay said, is the possibility that the S-300 will fall into the hands of Hezbollah or another terror organization. "They could use it against civilian air traffic," he said.
The decision announced Thursday by the main opponents to Assad to not join U.S.-proposed peace talks meant a diplomatic solution to the war was not in the offing. Interim president of the Syrian National Coalition George Sabra said that the organization would not attend talks while the Assad regime and its allies continue military activities in Syria.
"The National Coalition will not take part in any conferences or any diplomatic efforts in the face of an invasion by the Iranian militias and Hezbollah fighters," he said.
The SNC's Istanbul conference, now in its eighth day, has stalled with secular and Islamist blocs arguing over representation in the coalition.
"The conference is a failure ... there's no connection to what's happening on the ground," said Radwan Ziadeh, a former opposition spokesman and executive director of the Syrian Center for Political and Strategic Studies, a Washington-based opposition group.
SNC officials said the election of a new president and presidential committee, one of the gathering's primary purposes, may now not happen at all.
Sabra spoke of the worsening humanitarian situation in Qusair, where rebel groups have been unable to transport wounded rebels and civilians for medical care.
"We ask the International Red Crescent and other humanitarian organizations to go to Qusair immediately," he said.
The Geneva peace conference is supposed to happen June 15-16 but all sides are so far apart on how to achieve a lasting peace that its rationale is in doubt. The rebels insist the agenda must focus on the ouster of Assad, and they oppose the invitation of Assad's regime.
The Syrian regime has agreed "in principal" to attend the Geneva talks. However, the recent escalation of violence inside Syria has reduced the possibility of a diplomatic solution. Russia and Iran have openly supported Damascus with weapons and funding.
Russia insists the conference work on establishing a new political process in Syria that allows for Assad to remain, and Assad himself said Thursday he intends to run for re-election in 2014 though international poll observers say Syria's elections have not been fair.
Meanwhile, the risk of a wider war throughout the region increased Thursday. Speaking on Al Arabiya television, Gen. Salem Idris, head of the opposition's armed forces, threatened to launch attacks on Lebanon unless the Lebanese president forces Hezbollah to pull its forces out of Syria.
Starr reported from Istanbul; Chabin from Jerusalem