Brent crude oil steadied around$114 on Monday, after a week of gains, as a military strike against Syria looked less imminent and worries over possible Middle East supply disruptions receded.
U.S. President Barack Obama said he would seek congressional authorisation for punitive military action against Syria, almost certainly delaying any air strikes until Washington's summer recess ends on Sept. 9.
Oil got a boost, meanwhile, from improved factory activity in China and the euro zone,which stoked hopes of a revival in economic growth and oil demand growth.
Brent futures fell as low as $112.20 a barrel, down $1.81, but then rallied to around $114.45 by 1140 GMT. The U.S. benchmark in NYMEX after-hours trade plummeted to a low of $104.21, down $3.44, before bouncing back to around $107.10.
U.S. oil futures floor trading was closed on Monday for the Labor Day public holiday.
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"Oil would have been pushed lower had it not been for the China data," said Ben Le Brun, a market analyst at OptionsXpress. "The market is keeping an eye on the Middle East and developments in Syria, but we have seen some tensions easing."
Brent rose nearly 3 percent last week, its biggest weekly gain since July, on worries a strike by Western forces against Syria would disrupt Middle East oil exports at a time when markets are already coping with the loss of supplies from Libya and Sudan.
Before Obama announced his plan to seek approval from Congress, the path had been cleared for a U.S. assault. Warships were in place and awaiting orders, and U.N.inspectors had left Syria after gathering evidence on the use of chemical weapons.
The United States had originally been expected to lead a strike relatively quickly, backed by Britain and France. But British lawmakers last week voted against involvement, and France said on Sunday it would await the decision by the U.S.Congress.
David Hufton, managing director of London brokerage PVM Oil Associates, said he would not expect prices to fall far.
"The Syrian crisis has not gone away, and the consequences of non-intervention areas worrying as the consequences of intervention," Hufton said.
"There is only so much uncertainty that markets can take before they go into full scale safe-haven lockdown. With the Middle East in such turmoil, we would argue that oil will be regarded as the commodity safe haven."
China's factory activity expanded at its fastest in more than a year in August with a jump in new orders, official data showed.
In another sign that China may have averted a sharp slowdown in its economy, a separate private survey showed China's factory activity expanded for the first time in four months in August as domestic demand rebounded.
Strong orders for euro zone manufactured goods helped the bloc's factory activity rise at the fastest pace in over two years in August and led to backlogs of work for the first time since mid-2011, a survey showed on Monday.