U.S. stocks rose on Tuesday as strong commodity prices and a weak dollar before a Federal Reserve meeting gave a boost to Wall Street.

Financials also contributed to gains as Bank of America Corp shares rose after an analyst upgrade while Citigroup Inc gained 5.0 percent.

Crude oil futures rose 2.4 percent to $71.36 a barrel and copper for three-month delivery was up 1.2 percent, benefiting materials and energy companies.

U.S. Steel Corp rose 3.6 percent to $49.74 as metal prices advanced and Bank of America-Merrill Lynch upgraded the company's shares.

Positive comments from Citigroup lifted shares of Peabody Energy Corp and Massey Energy , which had the biggest percentage gains on the S&P energy index <.GSPE>.

The Fed is set to start a two-day monetary policy meeting on Tuesday, with a decision on interest rates due on Wednesday around 2:15 p.m. EDT.

We don't expect the rates to change, but there is some nervousness in the market about the statement that will folllow, said Joe Kinahan, chief derivatives strategist at thinkorswim, a division of TD Ameritrade Holding Corp.

The markets will look for any hints in the Fed's statement of winding down financial stimulus measures or comments about the strength of the economic recovery.

The Dow Jones industrial average <.DJI> was up 54.19 points, or 0.55 percent, at 9,833.05. The Standard & Poor's 500 Index <.SPX> gained 8.08 points, or 0.76 percent, at 1,072.74. The Nasdaq Composite Index <.IXIC climbed up 11.02 points, or 0.52 percent, at 2,149.06.

The euro reached a one-year high against the U.S. dollar on Tuesday as dealers took advantage of the greenback's gains in the previous session to resume selling ahead of the Fed meeting and a Group of 20 nations summit later in the week. The dollar index <.DXY> tumbled 0.9 percent.

Macy's Inc shares rose 6.8 percent to $18.99 after Citigroup upgraded the company.

Bank of America rose 2 percent to $17.63 and Citigroup gained 5 percent to $4.66.

In the energy sector, Peabody was up 6 percent at $40.48, and Massey Energy gained 5.4 percent to $33.07.

Declining stocks included health insurers, which limited gains on the S&P 500. The S&P managed healthcare sub index <.GSPHMO> fell 2.2 percent, weighed down by declines in UnitedHealth Group , down 3.2 percent, to $27.69 and Cigna Corp , which fell 1.6 percent to $31.24.

(Reporting by Angela Moon, Editing by Kenneth Barry)