(CNN) -- The U.N. Security Council renewed its Syrian observer mission for 30 days Friday, a small reprieve for a unit tasked with monitoring a failed peace plan.
Diplomats said that if the violence engulfing Syria doesn't recede enough for the observers to do their work, the U.N. Supervision Mission in Syria will be withdrawn.
The move came amid raging battles in the Syrian capital of Damascus and other cities and the government's resolve to take on its foes after a bombing Wednesday killed four members of President Bashar al-Assad's inner circle and government. They were al-Assad's brother-in-law, his defense minister, a security adviser, and the head of the national security bureau.
The mission's job is to monitor U.N. and Arab League joint special envoy Kofi Annan's six-point peace plan. It recently suspended its regular patrols because of the escalating violence.
The Security Council resolution calls on all parties to assure the safety of the observers and says the primary responsibility lies with Syrian authorities. It says the council wants to continue the observers' mission "only in the event that the secretary-general reports and the Security Council confirms the cessation of the use of heavy weapons and a reduction in the level of violence sufficient to allow UNSMIS to implement its mandate.
"The decision we took was to extend the UNSMIS mission for a final period of 30 days to allow it to withdraw safely and in an orderly fashion," said U.S. Ambassador to the U.N. Susan Rice. "And we hope very much that the withdrawal will be conducted with a principle priority placed on the security of U.N. personnel.
"We have also said in this resolution that, should -- in the unlikely event -- the situation on the ground change substantially and the government cease the use of heavy weapons and the level of violence become reduced to the extent that, indeed, UNSMIS again can not only operate freely but perform and fulfill the mandate that we gave it, then we would be prepared -- in that unlikely circumstance -- to revisit the question of whether UNSMIS has continued utility. "
This comes a day after Russia and China vetoed a resolution for new sanctions if Syrian government forces don't stop attacks against civilians. The resolution also would have called for renewing the 300-member U.N. observer mission for 45 days.
Russia and China -- major trade allies with Syria -- said they cast the vetoes because they want a more balanced resolution that calls on all sides to halt the violence. The vetoes, marking the third time they blocked tough resolutions on Syria in about 10 months, have sparked international condemnation.
"The U.S. approach will increasingly be to focus our efforts not so much in this council, which has hit a substantive dead end, but also to strengthen and intensify our work with other countries outside the Security Council, particularly the Friends of the Syrian People, which constitutes over a hundred countries that all asked for a Chapter VII resolution yesterday that, sadly, this council was not able to deliver," Rice said, referring to a resolution that would include the option of using force if other efforts fail.
"We will continue our political support to the opposition, our non-lethal assistance to the opposition. We will strengthen and intensify our sanctions, working with others to do the same. We will increase the amount of humanitarian assistance we provide," she said.
Fierce fighting has raged in the capital for days, dealing a blow to al-Assad's government and cracking the image of invulnerability that surrounded the regime.
Explosions rocked the Midan neighborhood in Damascus on Friday, where regime forces in tanks battled with fighters, according to opposition activists.
Syria state TV footage showed smoke rising, damaged buildings, and abandoned weaponry.
"When Midan people will return to their homes, they will witness and will be very happy how we cleared the neighborhood from the terrorists," a soldier is quoted as saying.
More than 80 people were killed Friday in Damascus and its suburbs, the opposition Local Coordination Committees of Syria said. The group reported at least 215 deaths throughout the country.
The government maintained its aim is to get rid of "terrorists" in the areas targeted. A Syrian security official told Al-Arabiya TV the military has started an operation to take over all neighborhoods in Damascus.
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Government helicopters shelled the suburban Damascus towns of Dumeir, Tayabiya and Harran al-Awameed, resulting in casualties and causing many people to flee, the LCC said.
Activists also reported the destruction of houses by missile fire in Aleppo and a siege of a mosque in the Daraa province town of Sanamein. At least 20 people were killed in Daraa province on Friday, the LCC said. It also reported deaths in Idlib, Hama Homs, Aleppo, Latakia, Swaida, and Deir Ezzor provinces.
Syrian soldiers fought "terrorists" on Thursday night in Deir Ezzor's Albo Kamal city, killing and wounding dozens, the state-run news agency said Friday. The government also said that a terrorist attack on a police school in Aleppo was repelled. Forces battled "terrorists and killed most of them," the news agency said Friday.
According to an activist in Albo Kamal, the city experienced the fiercest shelling since the start of the uprising.
"There is only one operational private clinic in the whole city now. The government's national hospital has closed down and other medical facilities were shelled. Five minutes ago, one shell fell right at the gate of that clinic, Aisha clinic. Many injured people are also being treated at mosques or homes. There is severe shortage of all kinds of medical supplies," the activist said.
CNN cannot independently confirm reports of violence because the government restricts access by foreign journalists.
Rebel fighters seeking control of the country's borders with Turkey and Iraq reported success in the latter.
The crossing points of Albo Kamal and seven additional security posts are in the hands of the rebels, a senior Iraqi army official in Anbar province said. He did not want to be named because he is not authorized to talk to the media.
Iraqi security forces have increased their military and security presence at the border in Anbar, the official said.
Late Friday, Iraqi Prime Minister Nuri al-Maliki released a statement, calling on Iraqis in Syria to return home.
"Given the difficult security conditions experienced by our brothers and our sons in Syria, we call on them -- men, women and children -- to return to their country ... And we tell them to please come back home, the place of your safety and honor. We will forgive all those who ... do not have blood on their hands so everyone can live in peace and security," he said.
Travelers along the Syrian-Turkish border told CNN they saw rebels controlling border points.
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A funeral was held Friday at the Martyrs Memorial in Damascus for three of the officials slain in Wednesday's attack -- Defense Minister Dawood Rajiha, Assistant Vice President Hasan Turkmani and the president's brother-in-law, Deputy Defense Minister Assef Shawkat.
Syrian media said there was a "significant official presence" at the funeral, a reference to high government officials. They included Vice President Farouq al-Sharaa and newly named Defense Minister Gen. Fahd Jassem al-Freij, who laid wreaths on the victims' bodies before they were buried, the state-run Syrian Arab News Agency said.
The head of the Syrian national security bureau, Maj. Gen. Hisham Akhtiar, who was injured in the blast, died Friday, Syrian state TV said, becoming the fourth top official killed in the explosion.
In another sign of what seems to be his crumbling power, the president did not appear in public after the killings but finally showed up on television Thursday during a swearing-in ceremony for the new defense minister.
The whereabouts of the president or the location of the ceremony remain unclear, though some have suggested he is not in the capital.
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The United Nations is estimating that more than 10,000 people have been killed in the violence since the crisis began in March 2011. But Rupert Colville, spokesman for the office of the U.N. high commissioner for human rights, said the United Nations hasn't been giving out overall death toll numbers since December "because it became impossible to verify the numbers in any meaningful way."
Opposition groups tracking deaths have issued higher tolls. The LCC, for example, estimates that more than 16,000 have died.
CNN's Amir Ahmed, Saad Abedine, Mohammed Tawfeeq, Ben Brumfield and Joe Sterling contributed to this report.