There is still no agreement among leaders of the world's richest nations on the final text of a declaration that will touch upon the protracted conflict in Syria, a Kremlin advisor said Thursday.

The leaders of the G8 -- Britain, Canada, France, Germany, Italy, Japan, Russia, and the United States -- will meet Friday and Saturday for a summit at the Camp David presidential retreat near Washington.

Former commander of Israel’s Air Forces warned on Thursday that his country’s air superiority is increasingly undermined by the proliferation of sophisticated surface-to-air missile systems throughout the region – in Syria, Lebanon, the Gaza Strip, and the Sinai Peninsula.

“The Israeli Air Force needs to be ready to fly in places where there is a threat to its superiority,” outgoing Air Force Maj.-Gen. Ido Nehushtan told The Jerusalem Post.

Bahrain on Thursday warned Iran to stop interfering in its internal affairs while affirming its support for a union between the six nations of the Gulf Cooperation Council.

Foreign Minister Sheikh Khaled bin Ahmed Al-Khalifa made the remarks a day after Iran called on its people to protest on Friday against the union that Gulf officials say will start with Bahrain and Saudi Arabia.

An Israeli tank shell fired into the Gaza Strip on Thursday wounded seven Palestinians, leaving two of them in critical condition, Palestinian medical officials told AFP.

The shell hit near the Karni crossing east of Gaza City, according to the medics.

Regime forces sent shells crashing into rebel stronghold Rastan early Thursday, the Syrian Observatory for Human Rights said, while calling on U.N. observers to rush to the town in central Homs province.

"The army is trying to gradually destroy Rastan," Rami Abdel Rahman, head of the Britain-based watchdog, told AFP.

Gulf monarchies must respect human rights, freedom of expression and allow for popular participation before turning the six-nation council into a union, Kuwait's parliament speaker said on Thursday.

"It is inevitable that the Gulf Cooperation Council (GCC) states will have no choice but to improve their relations to an advanced form of a union," Ahmed al-Saadoun said on his Twitter account.

Israeli forces demolished four structures in the Oz Zion and Ramat Migron settlement outposts in the West Bank early Thursday, prompting clashes that saw six people arrested, Israeli officials said.

"A temporary structure and water tower were demolished in Ramat Migron," civil administration spokesman Amir Koren told AFP. "The site was abandoned."

Egypt's Muslim Brotherhood has activated its formidable grassroots ahead of next week's presidential vote, but the Islamists may have hemorrhaged the support that helped them take parliament earlier this year.

Pressed in by the military rulers who took charge after president Hosni Mubarak's ouster last year, and facing an electorate impatient with the weak parliament's performance, the Islamists are desperate for executive power.

Seven people were killed and more than 20 wounded as gunmen raided the oasis town of Ghadames on the border with Algeria on Wednesday, Libya's government spokesman said.

"There were clashes in the city of Ghadames," Nasser al-Manaa said.

A new Palestinian government in the West Bank featuring 11 new faces was sworn in on Wednesday at a ceremony in Ramallah, in a move which angered the Hamas government in Gaza.

Ministers, including returning prime minister Salam Fayyad, took the oath of office in the presence of Palestinian president Mahmoud Abbas.