Oil hit multi-month lows this week on concerns that Spain's soaring bond yields could eventually lead to an international bailout for Madrid, but investors are hoping that any further monetary easing by the US central bank would boost liquidity and support prices.
Brent crude has already lost more than a quarter since peaking this year at $128.40 on March 1 as investors focused on the dimming outlook for global fuel demand rather than the supply disruption risks posed by sanctions on key producer Iran over its disputed nuclear programme.
Brent oil for August delivery was down 1 cent at $95.75 per barrel by 0434 GMT. It fell as low as $95.40 earlier, near Tuesday's trough of $94.44 - its lowest since Jan. 10, 2011.
US July crude, which expires on Wednesday, slipped 13 cents to $83.90 per barrel.
"The focus is still very much on Spain and Spanish bond yields. The levels they're currently at are just unsustainable," said Ric Spooner of CMC Markets.
"For the short term, the market is trying to price in the risk of contagion."
Spain moved closer to becoming the largest euro zone country yet to be shut out of credit markets after paying a euro era record price to sell short-term debt, with yields on longer-term bonds also at unsustainable levels at above 7 percent.
Investors were gearing up for the possibility of the Fed launching more stimulus measures to revive the world's top economy given a recent spate of dismal data, including last month's poor US jobs numbers.
"We have seen a clear weakening in the US economy. The strong employment numbers we'd seen earlier look to have been seasonal, so (the Fed) is going to have to look at doing something to improve jobs growth," Spooner said.
"The question is will they act now or hold off and use their firepower if or when the euro crisis gets worse?"
Besides the action by the US central bank, some investors were anticipating action from the Bank of England and the European Central Bank.
"We expect the ECB to cut interest rates in July and either start buying bonds again or launch another long term refinancing operation if Spanish and Italian bond yields fail to rally," Rupert Watson, Head of Asset Allocation, Skandia Investment Group, said in a note to clients.
"We also expect the Fed to provide more monetary stimulus and for the Chinese to cut interest rates. Finally, the Bank of England could announce a new round of quantitative easing."
The US central bank will release a policy statement at the end of its two-day meeting later on Wednesday, followed by a briefing by Chairman Ben Bernanke at 1815 GMT.