South Sudanese President Salva Kiir arrived in Khartoum on Saturday for his first visit since southern secession to discuss key unresolved issues, including Abyei and oil, that have undermined north-south relations.

Sudanese President Omar al-Bashir received his counterpart at the airport, alongside senior members of his cabinet, according to an AFP correspondent.

Eleven opponents of Syrian President Bashar Assad's regime were arrested after invading the country's embassy in Vienna and demonstrating on the balcony, police said Saturday.

They said some 20 people broke into the embassy in central Vienna's Landstrasse overnight, while dozens of others cheered them on in the street.

Russia expects a delegation of Syrian opposition politicians to visit Tuesday, a senior foreign ministry official said on Saturday.

"We are ready to meet them at the foreign ministry. This could happen on October 11 if they manage to arrive in time," deputy foreign minister Mikhail Bogdanov told the ITAR-TASS news agency.

Two Tibetan men set themselves on fire in southwest China in the latest self-immolation protest against the Chinese government, state media and a rights group reported Saturday.

The two former monks, 18-year-old Thongan and 20-year-old Tenzin, set themselves on fire in Aba county in Sichuan province's Aba prefecture Friday, according to the official Xinhua News Agency.

The White House on Friday called on Syrian President Bashar Assad to "step down now," warning he was taking his country down a "very dangerous path."

In a statement, spokesman Jay Carney condemned the killing of Kurdish opposition leader Meshaal Tamo as well as the beating of a prominent Syrian activist, saying it showed "again that the Assad regime's promises for dialogue and reform are hollow."

Eight Syrians were shot dead on Friday as thousands of people rallied against the regime of President Bashar Assad and in support of a newly formed opposition front, activists said.

The fresh surge of violence came as Russian President Dmitry Medvedev said Assad will have to give up power if he fails to implement reforms acceptable to the opposition, and the Syrian regime again blamed "terrorists" for the unrest.

Syrians rallied in their thousands after weekly prayers on Friday, pledging support to a newly-formed opposition front and calling for an end to President Bashar Assad's regime, activists said.

Iranian Foreign Minister Ali Akbar Salehi has condemned "heavy sentences" handed down by courts in Bahrain to pro-democracy Shiite protesters there, Tehran media reported on Thursday.

"The intensification of the crackdown on protesters and the heavy sentences will lead nowhere. Bahrain's government should take appropriate measures to respond to the demands and wishes of its people," Salehi said in remarks on Wednesday, Iran's state television reported on its website.

The Taliban opened fire on a bus in southern Afghanistan Thursday killing two civilians, including a child, and wounding 16 others, a local official said.

The attack came after the bus driver ignored demands from the militants to stop as he drove along a road in the troubled Gereshk district of Helmand province.

Turkey will continue searching for gas and oil in the Mediterranean waters, where the rival Cyprus government has already started drilling, the Turkish energy minister said.

"We will not leave the Mediterranean. There are zones that we had spotted earlier," Energy Minister Taner Yildiz was quoted as saying by the Anatolia news agency on Thursday.