U.S. stock index futures rose modestly on Wednesday as Spain said it would make wide austerity measures, further easing jitters over euro-zone sovereign debt woes.

The euro strengthened and European shares rose following the announcement. Investors have feared that Greece's debt crisis could spill over to other euro-zone nations with high debt loads, including Spain.

Spain's Prime Minister Jose Luis Rodriguez Zapatero said Madrid would slash civil service pay by 5 percent this year, freeze it in 2011 and axe 13,000 public sector jobs this year in a drive to meet European Union deficit targets.

Spain's move followed a 750 billion euro ($1 trillion) rescue plan late Sunday to stop the debt woes from spreading, cheering U.S. investors.

Shares of Walt Disney Co fell 2.2 percent to $34.98 in premarket trading after the entertainment and media group reported lower ratings and ad revenues as well as higher costs despite better-than-expected quarterly earnings.

U.S. investigators are probing whether Morgan Stanley misled investors about mortgage derivative products it sold and sometimes bet against, the Wall Street Journal reported, citing sources. Morgan Stanley shares were down 3.1 percent at $27.50 premarket.

Data on tap for the day includes international trade for March.

S&P 500 futures rose 3.9 points and were above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures added 24 points, and Nasdaq 100 futures gained 4.75 points.

The Dow and the S&P 500 fell in a volatile session on Tuesday on concerns about euro-zone debt.

(Reporting by Leah Schnurr; editing by Jeffrey Benkoe)

Morgan Stanley