Deadly violence raged across Syria on Sunday as regime shelling killed at least 18 civilians in the northwest while 28 rebels died in Damascus battling government forces, a monitoring group said.

The latest bloodshed came as Deputy Prime Minister Qadri Jamil was due to travel Monday to Moscow for talks with Russian Foreign Minister Sergei Lavrov on ways of ending the 28-month conflict.

Gunmen suspected of being members of al-Qaida kidnapped an Iranian diplomat in broad daylight on Sunday in the Yemeni capital Sanaa, police said.

"An Iranian diplomat was abducted on Sunday in Sanaa by armed men," a Yemeni security source told Agence France Presse, adding that the envoy was "taken to an unknown destination."

Iran on Sunday voiced opposition to a U.S.-mediated resumption of peace talks between Israel and the Palestinians, predicting the Jewish state would never agree to withdraw from occupied Arab lands.

Tehran "along with Palestinian groups expresses its opposition to the proposed plan and it's certain that the occupying Zionist regime will utterly not agree to withdraw from the occupied lands," foreign ministry spokesman Abbas Araqchi said, quoted by Iranian media.

The Arab League said on Sunday it supported the Palestinian stance on the announcement of resumed peace talks with Israel, but that it was skeptical of Israeli intentions.

The League "is forming a political support network for the Palestinian side in case it accepts to go to the negotiations with the Israeli side," Mohammed Sabih, deputy secretary general for Palestinian affairs and occupied Arab territories, told reporters.

A military court on Sunday rejected a bail application by Islamist cleric Abu Qatada, who faces terror charges in Jordan following his deportation from Britain, his lawyer said.

"The state security court today refused to release Abu Qatada on bail," Taysir Diab told Agence France Presse.

A road accident killed 15 soldiers and injured another 40 early on Sunday in Egypt's Nile Delta province of Beheira, a security source told Agence France Presse.

Their bus collided with a lorry on a highway in the province, leaving 15 of them dead and another 40 injured, the source said.

The Bahraini authorities have arrested three suspects linked to a car bomb that exploded outside a Sunni mosque south of the capital Manama, the government said on Sunday.

"Three people suspected of involvement in the terrorist act that took place near Sheikh Isa bin Salman mosque in Rifaa have been arrested," the interior ministry said on its Twitter account.

Israeli Prime Minister Benjamin Netanyahu warned ministers Sunday that renewed peace talks with the Palestinians will be tough, and said any draft treaty would be put to a referendum.

U.S. Secretary of State John Kerry on Friday said Israeli and Palestinian negotiators had agreed to meet to prepare a resumption of direct peace talks, stalled since 2010.

At least two of four Islamists killed by security forces in a raid southeast of Algeria's capital were members of al-Qaida in the Islamic Maghreb (AQIM), press reports said Sunday.

The four were aboard a vehicle ambushed in the town of Sour El-Ghozlane some 100 kilometers (60 miles) southeast of Algiers, reported Le Soir d'Algerie, citing reliable security sources.

Fighting raged on Sunday near Aleppo international airport and nearby air bases as the battle for Syria's second city entered its second year, a monitoring group said.

"Fierce clashes broke out at dawn near Aleppo international airport and Nairab air base," said the Syrian Observatory for Human Rights, also reporting fighting in the Suleiman Halabi district of the city, once Syria's commercial hub.