SYRIA (CNN) -- The U.N. monitoring mission in Syria will remain in place for now despite its activities being halted due to rising violence, its leaders said Tuesday.
Security Council members huddled behind closed doors with the mission's leader, Norwegian Maj. Gen. Robert Mood. Mood halted operations Saturday, reporting that the escalating violence between government troops and opposition groups was making it too risky for the monitors to do their jobs.
"I conveyed first and last that the suffering of the Syrian people -- the suffering of men, women and children in Syria, some of them trapped by fighting -- is getting worse," Mood said. However, he added, "I remain committed to the mission, in the position we are currently in. We're not going anywhere."
And Herve Lasdous, the United Nations' peacekeeping chief, told reporters that "for the time being, we have decided not to touch, not to modify" the observer mission.
About 300 monitors were dispatched to Syria to make sure that both sides in the conflict were following a six-point peace plan brokered by special envoy Kofi Annan. But an April cease-fire took place only in name, and fighting has increased sharply since late May. Heavy government shelling and the chilling massacres of civilians have been reported, and the monitors themselves came under fire at some points.
Mood said gunfire and shelling were "coming much closer" to his monitors, "and we have been targeted several times." He said he was reviewing conditions on a daily basis and hoped to resume operations soon.
Earlier Tuesday, a senior Obama administration official said Mood's report would influence how the United States and other members of the international community work with U.N. and Arab League envoy Annan on his proposal for a "contact group" on Syria and on how to deal with the regime of President Bashar al-Assad.
"The U.S. supports the idea of a contact group, which would bring together all nations that want to play a role in resolving the violence in Syria. But the U.S. remains opposed to including Iran, something which Annan thinks is a good idea," the official said.
"We've said from the beginning that if we could structure it (the contact group) for success ... particularly in promoting the post-Assad transition, that we are open to it but we are still working with Kofi and other countries."
U.S. President Barack Obama and Russian President Vladimir Putin discussed Syria at the G-20 meeting in Mexico on Monday. But the two made little headway on the crisis. In London, British Foreign Secretary William Hague stressed the importance of a "peaceful political transition and a "cessation of violence," but he added a grim caveat:
"At no stage have we been advocating a military intervention, but we do recognize the situation is so grave and deteriorating so quickly and such crimes are being committed, we cannot take any options off the table at the moment," Hague said.
Syrian opposition groups say more than 13,000 people have been killed since al-Assad's government started cracking down on anti-government protesters last year. The United Nations' latest estimate puts the death toll at more than 10,000.
At least 31 people were killed in Syria on Tuesday, according to the opposition Local Coordination Committees of Syria.
The state-run Syrian Arab News Agency said Tuesday that terrorists sabotaged oil pipelines in Homs and Deir Ezzor. The Syrian government blamed the violence on "armed terrorist groups," the vaguely defined entities it has consistently blamed over the past year.
During a question-and-answer session at the House of Commons, Hague commented on Annan's six-point peace plan. Mood's observer mission was tasked with monitoring an April cease-fire laid out in the plan and making sure the government adhered to the rest of the initiative.
He said he's accepted for a while that the Annan plan has not been working. He called the political situation in Syria "dire" and said world powers stand ready for robust action in the Security Council if the plan cannot be revived.
"It's wrong to give up completely on that plan because any peaceful settlement in Syria, the road to it is either through the Annan plan or something similar to the Annan plan," he said. "So it's important to persist in those efforts. We are doing that particularly in our talks with Russia."
The United States and its European and Arab allies have viewed Russia and China as obstacles to tough action against al-Assad.
Russia has refused to go along with the United States and other nations in calling for al-Assad to step aside. The nation, which has a lucrative arms trade with Syria, has blocked two Security Council resolutions that would have sanctioned the Syrian government.
Hague also said that a ship that was reported to be carrying arms to Syria has turned back -- apparently toward Russia.
U.S. officials have said that the cargo ship, MV Alaed, operated by the Russian company Femco, was headed for Syria with attack helicopters and munitions for the al-Assad regime from the port of Kaliningrad. The vessel had been off the north coast of Scotland, according to ship tracking data.
"We haven't given up the search for an internationally agreed-upon peaceful transition in Syria," Hague said, "but it is vital for such a transition to have the active support of Russia, and that's why we've attached such importance to the diplomacy of Russia in recent weeks and we will continue with those efforts."
Several Syrian "revolutionary" groups announced a new joint action committee Tuesday to consolidate efforts to oust al-Assad.
"While this joint committee is striving to overthrow the tyrannical regime in Syria, it calls upon all revolutionary forces to join them and work together to expedite the toppling of the regime, and to protect our people in Syria from its brutality," the Syrian Expatriates Organization said in an e-mail.
The groups include the General Commission for the Syrian Revolution and the Supreme Council for the Syrian Revolution, and the National Assembly.