Baghdad cancelled a $4.2 billion arms package with Russia on Saturday citing graft concerns and instead opted for new talks, ending a deal that would have made Moscow Iraq's second-biggest arms supplier.

In a bizarre sequence, however, the acting defense minister who negotiated the deal directly contradicted the prime minister's office, insisting nothing had been cancelled, a position that was swiftly denied by the premier's spokesman.

Twin car bombs at a military officers' club in southern Syria killed at least 20 soldiers on Saturday, a watchdog said.

The two bombs exploded minutes apart in the back garden of the club in the city of Daraa, the Syrian Observatory for Human Rights said.

Four people were killed and 26 injured late on Friday when a train derailed in central Iran, the official IRNA news agency reported.

The service from the southeastern city of Zahedan to the capital had 324 passengers on board, the news agency quoted the head of Iran's Red Crescent rescue corps, Mahmoud Mozafar, as saying.

Luis Moreno-Ocampo, the International Criminal Court's former prosecutor, said Friday that world leaders had a "good case" for asking NATO to prepare a warrant to arrest Syrian President Bashar Assad.

Moreno-Ocampo, an Argentine lawyer who was the ICC's first prosecutor, said given "it was absolutely clear" that as Syria's commander-in-chief Assad's forces had killed civilians, NATO could execute such a warrant.

The United States plans a $6.7 billion sale of 20 heavy cargo aircraft and five refueling planes to Saudi Arabia, the Pentagon announced Friday, in a deal to be approved by Congress.

The multibillion-dollar deal includes the cost of training, logistical support, parts and associated equipment for the aircraft, said a statement released by the Defense Department's agency for foreign arms sales.

More than 30 Syrian soldiers and rebels have been killed in clashes over the past week in a demilitarized zone of the Golan Heights facing Israeli-held territory, a monitoring group reported on Friday.

Israel's deputy prime minister Moshe Yaalon, meanwhile, warned Damascus it would act to defend its sovereignty if the fighting continued to spill over into the Israeli-occupied part of the Golan.

The number of people inside Syria in need of emergency humanitarian aid is expected to rise to more than four million early next year, while refugee numbers will soar to 700,000, the head of the U.N.'s humanitarian efforts said Friday.

"In the early new year... we're predicting that the numbers of people in need will exceed four million, up from 2.5 million," John Ging, who heads the U.N.'s Office for the Coordination of Humanitarian Affairs (OCHA) told reporters in Geneva.

The jailed son of Iran's former president Akbar Hashemi Rafsanjani denies reports that he has been charged with spying, the Mehr news agency quoted his lawyer as saying on Friday.

"Unfortunately a news agency and two news sites reported some allegations against Mehdi (Hashemi)," lawyer Mahmoud Alizadeh Tabatabee said.

Syria's largest armed opposition group is undergoing a drastic reorganization and relocating its leadership to rebel-held territory in a bid to win vital international support, a general told Agence France Presse.

Mustafa Sheikh heads the military council that presides over the Free Syrian Army (FSA) but which has been criticized for failing to bring order to a chaotic, umbrella group, some of whose members are implicated in suspected war crimes.

Veteran dissident George Sabra, a Christian former communist, was elected president of the Syrian National Council opposition bloc at a meeting in Doha on Friday.

The SNC's 41-member general secretariat, itself newly elected, chose Sabra, who garnered 28 votes, as part of efforts to revamp the group working to oust President Bashar Assad.