Saudi Arabia has expanded a buffer zone along its northern border with Iraq, where a U.S.-led military coalition is bombing Islamic State group extremists, official media said on Tuesday.

Mohammed al-Fahimi, a spokesman for northern region border guards, said "the depth of the border has been increased by 20 kilometers (12 miles)", the Saudi Press Agency reported.

Three people were sentenced to death and several others jailed in Saudi Arabia on Monday for Al-Qaida linked crimes including the deadly bombing of a foreigners' housing compound, official media said.

The attack on the Al-Mahya compound 11 years ago killed 17 people, mostly from Arab countries.

Gulf leaders agreed Sunday to return Saudi, Emirati, and Bahraini envoys to Qatar, ending eight months of tense relations with the gas-rich state over its support for the Muslim Brotherhood.

Earlier, leaders including the emirs of Kuwait and Qatar, the king of Bahrain and the UAE vice president arrived in Saudi Arabia for a previously unannounced summit aimed at resolving their differences.

Saudi Arabia on Thursday executed a Pakistani for heroin smuggling, bringing to six the number of convicted Pakistani drug smugglers beheaded over the past three weeks.

The sentence against Amin Allah Zar Gul was carried out in Riyadh after he was "found guilty of trying to smuggle heroin in his gut", the official Saudi Press Agency said.

Saudi Aramco operations are unaffected by a leak and fire which hit a diesel fuel pipeline near the capital Riyadh, a company statement received on Thursday said.

The state-owned firm is the world's largest oil company in terms of crude production and exports.

Saudi Arabia and France inked on Tuesday in Riyadh a deal to provide the Lebanese army with $3 billion worth of French weapons, with Riyadh footing the bill.

The deal, first announced in December, comes as the Lebanese army is battling gunmen and jihadists, including from the Islamic State group, in the north and along its northeastern border with war-torn Syria.

Al-Mustaqbal Movement leader ex-PM Saad Hariri reiterated on Monday that he was trying hard to push for the election of a new president in Lebanon.

In an interview with the French daily Le Figaro, Hariri said: “Lebanon's coexistence … is menaced by the paralysis of institutions amid a presidential vacuum.”

Foreign Minister Jebran Bassil lashed out at critics, saying that his meeting with his Syrian counterpart Walid Muallem in New York was held according to norms.

“The meeting was supposed to happen and it did,” Bassil told reporters in France.

Saudi Foreign Minister Prince Saud al-Faisal, whose country has joined the U.S.-led air strikes against Islamic State group militants in Syria, said Riyadh was ready to help Lebanon if it asked for assistance in its battle against jihadists.

In remarks carried by An Nahar newspaper on Thursday, al-Faisal said: “We have helped Lebanon to buy weapons through a $1 billion donation.”

Russian Ambassador Alexander Zasypkin revealed that Moscow decided to provide Lebanon with military assistance promised four years ago after it was encouraged by the Saudi grant to Lebanon.

“The Saudi grant was an incentive to revive the Russian grant and put it on the move,” Zasypkin told An Nahar newspaper in an interview published on Tuesday.