A Russian plane carrying humanitarian aid for Syrian refugees has headed to Beirut, Russia's Emergency Situations Ministry announced on Wednesday.

“An IL-76 aircraft has headed to the Lebanese capital,” Russia Today television quoted the ministry as saying.

French actor Gerard Depardieu, who was granted Russian citizenship by President Vladimir Putin, is set to film a thriller in Moscow and Grozny with British actress Elizabeth Hurley.

Hurley revealed on Twitter on Wednesday that she was shopping for costumes in Moscow after arriving to make the film with the veteran French actor.

Russia and the United States on Wednesday sought to limit the damage to already troubled ties from a new spy scandal that erupted when Moscow caught a blonde-wigged alleged CIA agent who was reportedly seeking information on the Boston bombings.

The suspected agent, who Moscow says was caught with a "typical espionage arsenal" of money and disguises, is said to have been working undercover as a low-ranking third secretary at the U.S. embassy.

Syria wants more details of a Russian and U.S. proposal for a peace conference before deciding whether to attend, Information Minister Omran al-Zohbi has said.

Interviewed late Tuesday by the Lebanese Al-Manar television, Zohbi also insisted that Syrian President Bashar Assad's future would be decided at the ballot box.

Russia on Tuesday ordered the expulsion of an alleged American CIA agent working undercover at the U.S. embassy who was discovered with a large stash of money trying to recruit a Russian agent.

Russia's Federal Security Service (FSB, ex-KGB) identified the man as Ryan C. Fogle -- third secretary of the political section of Washington's embassy in Moscow -- and said he had been handed back to the embassy after his detention.

U.N. Secretary General Ban Ki-moon will meet with Russian Foreign Minister Sergei Lavrov on Friday to discuss the Syria crisis, the Russian foreign ministry announced.

"Ban Ki-moon will travel to Russia from May 16 to 19" and will hold talks Friday on "questions of international importance, in particular the crisis in Syria," the ministry said in a statement Monday.

Despite a flurry of diplomatic activity aiming to end a war that has claimed more than 80,000 lives, Russia still shows no signs of abandoning its support for the regime of Bashar Assad.

U.S. Secretary of State John Kerry, British Prime Minister David Cameron and now Israeli Prime Minister Benjamin Netanyahu have all found time to meet President Vladimir Putin in the last few days in a new effort to find an international consensus.

Syria's opposition will consult with backers Saudi Arabia, Qatar and Turkey before it decides whether to take part in a peace conference proposed by the United States and Russia, its acting chief said Monday.

"It is too early to decide whether or not we will take part, because the circumstances of this conference are not yet clear. There is no agenda or calendar yet," said the opposition National Coalition's acting head George Sabra.

Russia on Monday condemned the twin weekend bombings near Turkey's border with Syria that Ankara blamed on groups close to the Damascus regime, calling for a thorough investigation.

"We strongly condemn these terrorist acts," the Russian foreign ministry said, expressing condolences to the victims of the "barbaric crime" that killed 48 people near the town of Reyhanli.

Israeli Prime Minister Benjamin Netanyahu is to hold talks on Tuesday with Russian President Vladimir Putin on the conflict in Syria, the Kremlin said, amid concerns Moscow plans to deliver advanced missiles to the Damascus regime.

"During the meeting an exchange of opinion is planned on key aspects of bilateral ties," the Kremlin said in a statement.