The Federal Reserve s unprecedented dose of stimulus to the economy during the recent financial crisis complicates the task of pulling back when the time is right, top central bank officials said on Friday.

Federal Reserve Board Governor Daniel Tarullo said on Friday that conducting periodic stress tests would require the cooperation of many regulators, not just the Fed.

The United States must ensure that the many efforts under way to make its financial system more robust are aimed at achieving common goals, a senior Federal Reserve official said on Friday.

Public disclosure of bank stress test results last year helped rescue the global financial system, and regulators should weigh some level of transparency in future tests, the Federal Reserve s leading figure on regulation said on Friday.

Treasury prices drifted higher Friday as investors moved to take advantage of sharply higher yields following a lukewarm auction of $118 billion in U.S. notes earlier this week.

Financial regulatory reform might potentially slow economic growth in the United States, St. Louis Federal Reserve President James Bullard said on Friday.

So the Obama administration is announcing a big new housing bailout later today. There are a number of details we don t know yet. A lot remains unclear. Apparently, the White House is going to encourage banks to write down the value of loans held by borrowers in modification programs.

Standard & Poor s Ratings Services said Friday that Greece s sovereign credit ratings and outlook won t be affected by the bailout plan from the Economic & Monetary Union and the International Monetary Fund.

The U.S. Treasury may unveil a preset trading plan next month for the sale of its 27 percent stake in Citigroup, Bloomberg reported.

The Federal Reserve Board on Friday approved First Niagara Financial Group Inc s application to become a bank holding company in connection with its acquisition of Harleysville National Corp .