U.N. Special Coordinator for Lebanon Sigrid Kaag emphasized that the Lebanese officials are primarily accountable for the political and economic situation, stressing that the long-term relations with regional countries might play a positive role in several pressing issues.

“The primary responsibility lies on the Lebanese officials whether regarding the political or economic situations,” said Kaag in an interview with Iran's News Agency IRNA on Monday.

Two Saudi border guards have been killed in an attack from Yemen by Iran-backed rebels, Riyadh's official news agency and a rebel-run news site said.

Sergeants Ali al-Ghazwani and Sarwi al-Saeed were "martyred while carrying out their duty in protecting the country's borders from rebel aggressors" on Sunday, the official SPA said, quoting a statement by the Saudi-led coalition.

Saudi authorities on Wednesday beheaded a Syrian for drug trafficking in the kingdom's northwestern region of Jawf, the interior ministry announced.

Omar al-Nasser was arrested while smuggling a "large amount of amphetamines," the interior ministry said in a statement on the official SPA news agency.

Syrian opposition figures head to Moscow this week although they are unlikely to welcome Russia's plan for a new anti-jihadist coalition that would include embattled Syrian President Bashar Assad.

Moscow has since June been pushing a plan for a broader grouping than the U.S.-led coalition fighting the Islamic State (IS) group, to include Syria's government and its allies.

President Barack Obama's administration vowed to press ahead with a half-billion-dollar mission to train Syrian opposition fighters Tuesday, despite fears that its initial failures have dented U.S. credibility. 

After the routing of a 54-strong U.S.-trained force by al-Qaida allied rebels, Pentagon spokeswoman Commander Elissa Smith told Agence France Presse there was no plan to pause or scale back the program.

Saudi Arabia's foreign minister on Tuesday poured cold water on Russian calls to join forces with the Syrian authorities against Islamic State jihadists, insisting it would never work with President Bashar Assad. 

Moscow -- one of Assad's few remaining allies -- has called for coordination between the Syrian government and members of an international coalition fighting the extremist group, which controls swathes of territory in Syria and Iraq.

Saudi-backed forces loyal to Yemen's exiled government captured more territory from Iran-backed rebels Tuesday as they pressed an advance that has seen them retake large parts of the war-torn country's south.

Aid agencies voiced alarm over the "catastrophic" humanitarian situation in the impoverished nation, devastated by months of fighting.

Italy's billionaire former leader Silvio Berlusconi may sell his lavish Mediterranean villa, made famous by lurid photos of cavorting guests, to the Saudi royal family, Italian news reports said Monday.

Crown Prince Mohammed bin Nayef, first in line to the Saudi throne, was given a personal tour of the Villa Certosa property last week and might take it off the ex-premier's hands for some 500 million euros ($550 million), they said.

Human Rights Watch on Monday urged the Saudi Arabian authorities to free a writer and commentator arrested after he called on television for political reforms in the absolute Gulf monarchy.

Zuhair Kutbi, 62, was detained on July 15 after an interview in June in which he called for reforms including "transforming the country into a constitutional monarchy and combating religious and political repression," the New York-based HRW said.

Saudi Arabia beheaded one of its citizens on Monday after he was convicted of murdering a relative, the interior ministry said, adding to a sharp increase in executions this year.

Saleh al-Zahrani was convicted of shooting dead Attiya al-Zahrani during a dispute between them, said the statement carried by the official SPA news agency.