U.S. crude oil price edged up on Friday on a weaker dollar as U.S. first-quarter economic growth missed expectation.

The Commerce Department said that U.S. GDP expanded 2.2 percent in the first quarter, down from 3.0 percent in the fourth quarter 2011, also missing the consensus forecast of 2.3 percent to 2.5 percent. The slow-down of U.S. economic recovery weighed on the markets, causing oil's losses in the earlier trading session.

However, the softer-than-expected GDP data also posed pressure on the dollar. The dollar index, which tracks the greenback's performance against a basket of currencies, fell about 0.6 percent. A weaker dollar made the dollar-denominated crude more attractive, pushing the prices up.

The rise of U.S. consumer confidence also provided supports. According to a closely-watched survey by Reuters/University of Michigan, U.S. consumer confidence index rose to 76.4 in April, near to a peak hit last year.

And since the Federal Reserve's post-meeting statement on Wednesday, the crude kept be boosted by the investors' hopes for more monetary easing.

Light, sweet crude for June delivery gained 38 cents, or 0.36 percent to settle at 104.93 dollars a barrel on the New York Mercantile Exchange. For this week, it rose 1.88 dollars, or 1.82 percent.

But analysts expected losses in the coming weeks as the world crude supplies tended to rise, partly helped by the production recovery in Libya and tension eased over Iran's nuclear program. U. S. Energy Information Administration reported on Friday that world oil and motor fuel supplies exceeded demand by 500,000 barrels per day in March and April, curbing worries about supplies disruption on Iran sanctions.

But in London, pressured by the cuts of Spain's credit ratings, Brent crude for June delivery fell slightly by 9 cents to close at 119.83 dollars a barrel. For this week, it rose 1.07 dollars, or 0. 90 percent.