At least 143 people were killed in violence across Syria on Thursday, among them 100 civilians and 43 government troops, activists and a rights group said.

"This has been one of the bloodiest days in Syria since the anti-regime revolt broke out in March last year," Observatory head Rami Abdel Rahman told Agence France Presse.

Palestinians said Thursday they had recovered the bodies of two militants from a tunnel damaged by an Israeli air strike on Gaza, raising to 10 the death toll in the territory since Monday.

Thaer Mohammed al-Bik, 30, and Mohammed Zuhair al-Khaldi, 26, were killed by gas fumes as they carried out an inspection of the tunnel hit by Israeli fire on Tuesday, the military wing of Gaza's ruling Hamas movement said.

The speaker of the Iraqi parliament said on Thursday that he had ordered a halt to all work at the legislature until concrete blast walls removed in recent days are put back.

Osama al-Nujaifi said that if the government were confident that the security precaution was no longer necessary, then all of the protective barriers around the entirety of the Green Zone, Baghdad's fortified government and embassy compound, should be removed.

Egypt was on edge on Thursday after the Muslim Brotherhood warned of "confrontation" between the people and the ruling generals unless its candidate is named to succeed toppled president Hosni Mubarak.

U.N. leader Ban Ki-moon discussed the situation in Syria on Thursday with Iran's President Mahmoud Ahmadinejad, a U.N. spokesman said, amid a new diplomatic push to end the crisis.

Ban and Ahmadinejad also spoke about the showdown over Iran's disputed nuclear programs during the talks on the sidelines of the United Nations Conference on Sustainable Development in Rio de Janeiro, said U.N. spokesman Martin Nesirky.

French police on Thursday detained Iraqi official Sadeq Kazem for questioning after a member of the Iranian opposition filed a complaint alleging torture and war crimes, a judicial source said.

Kazem runs Camp Liberty, where People's Mujahedeen of Iran militants are being moved from their long-time base of Camp Ashraf, the scene of deadly raids by Iraqi forces in 2009 and 2011.

U.N.-Arab League envoy Kofi Annan will hold a press conference with the head of the U.N. mission in Syria Robert Mood in Geneva on Friday, the United Nations said.

The conference follows the weekend suspension of patrols by the 300-strong observer team amid intensifying violence.

A Tunisian military plane destroyed three cars loaded with weapons that were driving just north of the country's southern border with Algeria and Libya, the official TAP news agency said Thursday.

The plane attacked the vehicles after their occupants opened fire on it as it patrolled the southern zone of Satah al-Hassan 100 kilometers (60 miles) north of the triple border overnight Wednesday, TAP reported.

Egypt on Thursday braced for a showdown between the military and the Muslim Brotherhood as the electoral commission delayed announcing the winner of a presidential poll claimed by the Islamists.

A delay in announcing the results from the run-off, which had been due on Thursday, heightened Brotherhood fears of a "soft coup" by the ruling military, which has already disbanded the Islamist-led parliament and granted itself sweeping powers.

Russian Foreign Minister Sergei Lavrov said on Thursday that any peace plan for Syria that calls on President Bashar al-Assad to leave power and go into exile was not workable because he would not quit.

"A scheme according to which President Assad should leave somewhere before something happens in terms of a cessation of violence and a political process, this scheme does not work simply from the very start," the Interfax news agency quoted Lavrov as saying. "It is infeasible because he will not leave."