Brent crude plunged to a six-month trough below $99 a barrel on Tuesday in a two-session drop of more than $10, after a U.S. credit downgrade intensified fears about a global slowdown in demand for energy, sending commodities markets tumbling.

Brent crude fell as much as $5 to $98.74 a barrel, the lowest intraday price since February 8, and was down $4.06 at $99.68 by 0200 GMT, down from an April peak above $127. U.S. crude fell $4.83 to $76.48, after touching $75.71, its lowest since September 2010.

I'm surprised how far it has fallen in all markets, this is panic, said Jeremy Friesen, a commodity strategist at Societe Generale in Hong Kong.

Demand hasn't pulled back in the past day, it's just speculation that it will, but as precipitously as markets are falling, we don't have time to wait for economic data. There are some serious risks to the global economy, so there will be expectations that policymakers will be aggressive in shoring up confidence.

Investors await the Federal Open Market Committee meeting on Tuesday for clues to whether the U.S. central bank might ease monetary policy further.

Asia's stock markets took a beating on Tuesday, following deep losses on Wall Street, as investors weigh the risk of another U.S. recession and a worsening sovereign debt crisis in Europe.

Major indexes across the region fell between 2 and 5 percent, following a drop of more than 6 percent on Wall Street in the first trading session since the historic downgrade of the United States' AAA credit rating by Standard & Poor's.

U.S. President Barack Obama on Monday called for urgent action on the budget deficit, but his proposal on taxes was promptly rebuffed by Republicans. The G7 finance ministers' and central bankers' pledge on Sunday to help smooth markets if needed provided little solace.

The S&P downgrade added to concern about energy demand in the world's top oil consumer. U.S. gasoline demand for July fell to the lowest level since 2003, according to data from the U.S. Energy Information Administration.

China's inflation rate, which analysts fear could curb Beijing's ability to stimulate demand to offset a global slowdown, turned out to be higher than expected.

Annual inflation in China rose to 6.5 percent in July, its highest since June 2008, putting the central bank in a bind as it tries to rein in prices without dragging down an economy facing increasing threats from abroad.

Oil's plunge over the past two days has taken prices below the comfort zone for some of the more hawkish members of the Organizations of the Petroleum Countries.

OPEC Ministers will meet if prices continue to fall, Iran's OPEC governor, Mohammad Ali Khatibi, said on the Oil Ministry news website SHANA on Friday.

Analysts warned oil prices could fall further if a second recession takes hold, but both Merrill Lynch and Goldman Sachs maintained their 2012 price forecasts.

We believe that WTI crude oil prices could briefly drop to $50 under a recession scenario, Merrill Lynch said in a note, but it maintained its 2012 average forecast for U.S. crude at $102 and its forecast for Brent next year at $114.

Brent broke below the key 200-day moving average on Monday, extending a correction that has taken more than 21 percent off prices from their April peak.

Gold surged 1.7 percent on Tuesday to a record above $1,740 an ounce, while industrial metals and agricultural commodities slumped.

(Reporting by Alejandro Barbajosa; Editing by Clarence Fernandez)