Meanwhile, EU foreign ministers tightened sanctions against the Assad regime, while Russia offered conflicting signals as to whether it still stood by a government abandoned by all but a few stalwart allies.RELATED:Syria rebels retreat after seizing area near capital'Iran transporting weapons to Syria through Turkey'An official Syrian source told the state news agency SANA that the Arab initiative, which would have Assad hand power to a deputy pending elections, was a “conspiracy against Syria.”“Syria rejects the decisions of the Arab League ministerial council... and considers them a violation of its national sovereignty and a flagrant interference in its internal affairs,” the source said.“The decisions taken in Cairo may be a game-changer, also for the Security Council,” Germany’s UN Ambassador Peter Wittig told reporters. The Arab plan fell short of asking for the intervention of the UN Security Council, but it did ask for that body’s endorsement.“The Arab League decided to seek the Security Council’s endorsement for its decisions... This is something that council members couldn’t easily ignore or oppose,” Wittig said, in apparent reference to Russia and China, both veto-wielders that have blocked tough action against Damascus.Lebanese Foreign Minister Adnan Mansour – who represents the Syria-allied Shi’ite Amal movement – criticized the League’s move, saying its ministers had taken an “unbalanced” approach to the crisis by disregarding violence perpetrated by Assad’s opponents.“The Assad regime may dismiss the Arab League plan as a conspiracy, but even the conspiracy-prone Syrian people no longer believe Assad has any credibility left,” Michael Rubin, a resident scholar at the American Enterprise Institute, told The Jerusalem Post.The EU added 22 people and eight entities to a list of banned people and groups and said Assad’s repression was unacceptable.“The message from the European Union is clear,” the EU’s foreign policy chief, Catherine Ashton, said. “The crackdown must stop immediately.”The tougher Syria sanctions came on the same day that the EU unveiled an “unprecedented” oil embargo against Syria’s patron Iran.Syria’s other major international partner is Russia. On Monday, Moscow said it had “exhausted its diplomatic resources” in trying to help Assad, even while new reports emerged the Kremlin had sold its ally dozens of training jets.Russia has resisted pressure to call for Assad’s resignation and, with China, blocked a Western-crafted UN Security Council resolution that would have condemned the Syrian government’s crackdown.But Russia can do no more, state-run news agency Itar-Tass quoted Mikhail Margelov, a senior lawmaker who is President Dmitry Medvedev’s special Africa envoy and has also engaged in diplomacy over Syria, as saying.“[Our] veto on the UN Security Council resolution was the last instrument allowing Bashar Assad to maintain the status quo in the international arena,” Margelov said. The veto “was a serious signal to the president of Syria from Russia.This veto has exhausted our arsenal of such resources,” said Margelov, who is chairman of the international affairs committee in Russia’s upper parliament house.Burhan Ghalioun, head of the main opposition Syrian National Council, welcomed the Arab League initiative, saying it “confirms that all Arab countries today consider the tyrannical regime of Bashar Assad to be finished and that it must be replaced.”The Sudanese general who heads the Arab monitoring mission said violence had dipped in the past month, contradicting accounts by activists who say at least 600 people were killed.“After the arrival of the mission, the intensity of violence began to decrease,” Mohammed al-Dabi told a news conference at the Cairo-based Arab League, saying the monitors had logged only 136 deaths on both sides since they began work.“Our job was to check what is happening on the ground and not investigate it,” Dabi said.His role as chief monitor has displeased Assad’s critics given that he has held senior military and government posts in Sudan, including in Darfur, where the International Criminal Court prosecutor says the army carried out war crimes and the United Nations says 300,000 people may have died.Saudi Arabia, an adversary of Syria’s ally Iran, undermined the mission’s credibility when it withdrew its own monitors on Sunday, accusing Damascus of defying an earlier Arab peace plan.“It takes a lot in the Arab world when even a regime’s conspiracies are no longer believed,” Rubin said. “That said, nothing the Arab League does is meant for more than public relations.Arab diplomats are too divided to ever agree on anything beyond basic imagery.”The United Nations says more than 5,000 people have been killed by the security forces since an anti-Assad revolt began in March.Reuters contributed to this report.