The U.S. central bank has decided to extend one of its stimulus measures in a new effort to boost the country's sluggish economy.

Federal Reserve policy makers decided Wednesday to expand a program to replace short-term government bonds with longer-term notes, shifting another $267 billion through the end of 2012. The central bank said the renewed policy — which had been set to expire at the end of June — “should put downward pressure on longer-term interest rates” to increase more borrowing, spending and economic growth.

The Fed, however, did not sanction any new measures to advance the world's largest economy. The policy makers said they are “prepared to take further action as appropriate to promote a stronger economic recovery.” The central bank renewed its plan to keep its benchmark lending rate at between zero and a-quarter-of-one-percent at least through late 2014.

The central bank said the American economy has been expanding “moderately” this year, but that growth in the country's labor market has slowed in recent months and its jobless rate “remains elevated.” It also said U.S. consumer spending — which drives about 70 percent of the national economy — “appears to be rising at a somewhat slower pace” than earlier in the year.

The Federal Reserve said inflation in the U.S. has declined, a reflection of the fact that world oil prices have dropped, cutting the cost of gasoline for motorists.

American employers — the heart of the world's largest economy — have sharply cut back their hiring in the last two months. The country's jobless rate edged higher to 8.2 percent in May after falling during late 2011 and the early months this year. Meanwhile, a government report this week showed that the number of job openings in the country is falling.

But U.S. officials — including President Barack Obama — are also worried about the continuing governmental debt crisis in Europe's 17-nation euro currency bloc, one of the largest trading partners for U.S. exporters.

Republican presidential challenger Mitt Romney has made the state of the American economy — and Mr. Obama's oversight of it — the focal point of his campaign to win the White House in the November election. Surveys show many voters do not think Mr. Obama has improved the economy enough during his three-and-a-half years in office. The president has repeatedly noted that the economy is emerging from the depths of the country's worst downturn since the 1930s, but not at the speed he would like.