* Euro zone growth lifts spirits, world stocks rise
* U.S. stocks up slightly after opening
* Dollar at 3-week low vs euro
* Gold rises to three-month highs
NEW YORK, Feb 14 Signs of a gradual improvement in euro zone growth helped lift world stocks on Friday and pushed the euro to its highest in almost three weeks against the dollar.
U.S. stocks opened up slightly, putting the S&P 500 on track for its first two-week winning streak of the year, while gold rose to three-month highs above $1,300 an ounce following the dollar's weakness.
Investors gave a cautious thumbs up to political changes in Italy.
Italy's center-left leader, Matteo Renzi, forced out Prime Minister Enrico Letta on Thursday after Letta failed to pass major reforms. The new government will be Italy's third in a year, but the hope is Renzi can revive efforts to streamline the euro zone's third-largest economy.
The MSCI global stock index climbed 0.4 percent, while stocks in Milan were Europe's best performers, rising 1.5 percent, compared with a 0.4 percent gain for the pan-European FTSEurofirst 300 index.
Fourth-quarter gross domestic product reports in Germany and France both exceeded expectations. That meant euro zone GDP growth as a whole also beat forecasts - 0.3 percent versus a projected 0.2 percent. That reduced the pressure on the European Central Bank to cut interest rates at its next meeting.
On Wall Street, the Dow Jones industrial average rose 49.44 points or 0.31 percent, to 16,077.03, the S&P 500 gained 3.42 points or 0.19 percent, to 1,833.25 and the Nasdaq Composite dropped 0.54 points or 0.01 percent, to 4,240.132.
In the currency market, the euro rose as high as $1.3715 .
Gold rose to three-month highs above $1,300 and looked set to post its biggest weekly gain in six months. Spot gold was up 1 percent to $1,315.10 an ounce after earlier rising 1.3 percent to its highest since Nov. 8 at $1,319.80.
The weaker dollar also helped Asian emerging-market currencies gain for the week. The Indonesian rupiah was near a 11-week high after a report showed the country's current account deficit narrowed in the fourth quarter.
In the bond markets, benchmark 10-year Treasury note prices were down 4/32, with a yield at 2.75.
U.S. bond yields rallied this week after the U.S. Congress approved an increase in the debt limit and incoming Federal Reserve Chair Janet Yellen maintained the central bank's commitment to gradually withdraw its stimulus.
In the energy market, oil prices slipped, with U.S. crude down 38 cents at $99.97 and Brent crude down 12 cents at $108.40.