U.S. stocks were slightly higher on Monday as euro zone finance ministers approved a massive emergency aid plan for debt-plagued Greece, removing

some sovereign debt worry.

Earnings season gets underway after the close of trading, with Alcoa Inc , the aluminum major and Dow component, due to report results.

Heavy equipment maker Caterpillar Inc was the top boost to the Dow, up 1.9 percent to $66.50 after a brokerage upgraded the stock to outperform from neutral.

Euro zone ministers signed off on a 30 billion euro ($40 billion) rescue package for Greece Sunday, but stressed that Athens had not yet asked that the plan to be activated.

A German government spokesman removed some steam from the announcement after saying the European leaders would have to agree at a special meeting to activate the aid mechanism.

It (puts on the) backburner the issue for some time unless the summit thing goes badly. Then that will be an issue, said Stephen Massocca, managing director at Wedbush Morgan in San Francisco.

The Dow Jones industrial average <.DJI> gained 14.66 points, or 0.13 percent, to 11,012.01. The Standard & Poor's 500 Index <.SPX> rose 2.46 points, or 0.21 percent, to 1,196.83. The Nasdaq Composite Index <.IXIC> advanced 1.70 points, or 0.07 percent, to 2,455.75.

With earnings season kicking into gear, other major companies set to report earnings this week include General Electric Co , Google Inc , Intel Corp and JPMorgan Chase & Co .

We are going to have an excellent earnings season. How much of that is already in the market, that's the million-dollar question, said Massocca.

Mirant Corp led a new batch of mergers and acquisition activity after the big U.S. power producer agreed to take over rival RRI Energy Inc , while Palm Inc

is reportedly looking to sell itself.

Mirant shares surged 17.3 percent to $12.60, and RRI Energy gained 12.2 percent to $4.43. Palm shares jumped 13.8 percent to $5.87.

(Reporting by Chuck Mikolajczak; editing by Jeffrey Benkoe)