WASHINGTON — The Federal Reserve on Tuesday offered its most optimistic view of the U.S. economy since the recession ended, even as Japan’s nuclear crisis stoked new worries around the world.

The economic recovery is on “firmer footing” and the jobs market is “improving gradually,” the Fed declared in its statement released at the conclusion of its meeting in Washington.

That’s a more upbeat tone from its previous meeting on Jan. 26, when Fed policymakers said the rate of economic activity was “insufficient” to bring about “significant improvement” in the job market.

The Fed downplayed inflation risks, and it dropped the phrase “disappointingly slow” in describing the progress made lowering the nation’s unemployment rate. That reflects a drop of nearly a full percentage point in just three months – the sharpest decline in unemployment since 1983.

In a unanimous decision, the Fed said it was maintaining the pace of its $600 billion Treasury bond-purchase program to help the economy grow and to lower unemployment, which now stands at 8.9 percent.

The Fed made no mention of Japan’s crisis, which caused stocks to plunge earlier in the day. But the more positive outlook from the Fed helped Wall Street recover some ground from a rough start.