By Ros Krasny

CHICAGO, June 14 (Reuters) - U.S. central bank officials are focusing their rhetoric on preventing a coming storm of inflation, but reports due this week could show that deflationary forces still pose a risk.

At the same time, an historic meeting of leaders from the four so-called BRIC countries to discuss the global financial crisis, could stir up new jitters about the United States' ability to fund massive budget deficits.

The longest U.S. downturn since the Great Depression is likely to end soon, and expressing worries about inflation has become de rigueur -- even while consumer prices are falling for the first time in decades.

Commodity prices .CRB are up 30 percent since March and crude oil prices CLc1 have doubled since February, suggesting the deflation threat may have passed.

But some economists fear a deceleration of wage inflation in the United States, given forecasts for the ranks of the U.S. unemployed to continue rising into 2010, with a potential jobless peak near 11 percent versus the current 9.4 percent.

Wage inflation is sometimes cited by the Federal Reserve as a relatively "sticky" indicator of price trends, compared with more transitory factors such as gasoline prices.

"Wage pressures are easing rapidly while firms' pricing power remains limited," said Anna Piretti, economist at BNP Paribas in New York. "It is still premature to put deflationary worries aside."

Wage inflation tends to trough about 3 years after the onset of a recession, she said.