GLOBAL MARKETS-Oil falls on OPEC, euro slips on debt worries

* OPEC mulls boosting production for 1st time in 2 years

* Euro slips for 2nd day on euro zone debt concerns

* Greek 10-year yields hit euro-era high

* U.S. stocks rise on oil price relief (Updates with US markets open; changes byline, dateline, previous LONDON)

By Walter Brandimarte

NEW YORK, March 8 (Reuters) - Oil prices fell on Tuesday as OPEC considered boosting production for the first time in more than two years, while the euro slipped for the second day on renewed euro zone debt worries.

U.S. stocks rose as investors greeted the fall in oil prices with relief, but a drop in base metals, such as copper, drove shares of miners lower, weighing on European equity markets.

The recovery in stocks appeared tentative as investors feared that unrest in Libya and the Middle East could still drive oil prices up, one day after they hit a 2-1/2-year high.

An official oil output increase by the Organization of the Petroleum Exporting Countries would signal the group's determination to cap prices, but continued violence in Libya left investors jittery.

OPEC oil producers are consulting about a supply boost, Kuwait's oil minister said, but many in the group remain skeptical. [ID:nLDE7270Q8]

"At the moment, I think we just remain nervous -- the situation in the Middle East is still fluid," said Frank Lesh, a futures analyst and broker at FuturePath Trading LLC in Chicago. "We'd like to see a little more clarity there, and we certainly don't have that."

Brent crude prices dropped 1.45 percent to $113.37 per barrel, while U.S. light crude futures were 0.6 percent lower at $104.80.

The three major U.S. stock indexes traded higher after starting the session flat.

The Dow Jones industrial average <.DJI> was up 64.56 points, or 0.53 percent, at 12,154.59, while the Standard & Poor's 500 Index <.SPX> rose 6.54 points, or 0.50 percent, at 1,316.67. The Nasdaq Composite Index <.IXIC> gained 12.61 points, or 0.46 percent, at 2,758.24.

In Europe, the FTSEurofirst 300 <.FTEU3> index of top shares was little changed at 1,144.47 points, after seesawing between positive and negative.

GREEK YIELDS AT RECORD HIGH

The euro fell against the dollar as concerns about the debt situation of peripheral euro zone countries outweighed expectations of an interest rate hike by the European Central Bank next month.

Concerns about Europe's debt problems have been on the rise since Moody's cut Greece's credit ratings by three notches on Monday, signaling that more downgrades are on the way.

Greece's borrowing costs spiked on Tuesday, with yields paid by 10-year government bonds climbing to 12.946 percent, their highest since the launch of the euro currency.

The euro fell 0.59 percent to $1.389. It had climbed above $1.40 after ECB president Jean-Claude Trichet said last week that euro-zone interest rates could rise as early as next month.

"The problem with the interest rate driven trade and Trichet's hawkish comments is that you have to see the other issues behind it," said John McCarthy, director of foreign exchange at ING Capital Markets in New York. "Higher rates will be devastating on the peripheral countries." (Additional reporting by Chuck Mikolajczak, Nick Olivari, Brenda Goh and William James; Editing by Padraic Cassidy)