* Fed holds aggressive stimulus in place * Prices fall as investors ponder extent of recent rally * Cyprus now seeking a new loan from Russia By Luciana Lopez NEW YORK, March 20 Prices for U.S. Treasuries slid on Wednesday as investors weighed the extent of a rally this week sparked by a plan to tax Cypriot bank accounts, with the Federal Reserve keeping policy on hold. The Fed will keep pumping about $85 billion into the economy each month until the job market shows marked improvement, though Chairman Ben Bernanke said the bank could change the rate of purchase as the economy improves. And while there are risks to persistently low interest rates, the bank can handle those hazards for now, Bernanke said at a news conference concluding a two-day policy meeting. "In the committee's view these costs remain manageable but will continue to be monitored, and we will take them into appropriate account as we determine the size, base and composition of our asset purchases," he said. Analysts said there was little surprising in the Fed's statement. "We have been and continue to take the Fed at its word," said Henry Smith, chief investment officer at Haverford Trust Co in Philadelphia. "The fact is, the Fed is committed to this, call it an all-in policy, for the foreseeable future." Prices pared losses slightly on the news but remained lower on the day. The benchmark 10-year note was last trading down 14/32 in price to yield 1.953 percent. Prices for the 30-year bond briefly spiked even lower after the news but then pared losses. Those bonds were last down 1-05/32 in price to yield 3.192 percent. Prices for U.S. Treasuries gained this week after fears that a tax on bank deposits to help fund a bailout for Cyprus could be adopted elsewhere in the euro zone, including Italy and Spain. Cypriot lawmakers overwhelmingly rejected the deeply unpopular tax on Tuesday, and the island nation is now pleading for a new loan from Russia to avert a financial meltdown. There's now some recognition "that this market has gone a little too far on a short-term basis, though that doesn't mean it will be a straight line back the other way," said Greg Faranello, a Treasuries trader at Societe Generale in New York. And with the euro zone debt crisis still unresolved, easy solutions will be few, said Wilmer Stith, portfolio manager of the Wilmington Broad Market Bond Fund in Baltimore. "At the end of the day the slow train ride that they're on of austerity and rebuilding will take several years," he said. Several banks have raised their submissions in the London interbank offered rate (Libor) this week, spurring some concerns that banks and investors may again be pulling back on loans made in the euro zone region. Despite this move, traders said there were not yet any signs that Cyprus' problems threaten broader contagion. "There are some accounts that are taking a wait and see approach, but there has been no systemic issue," said Kenneth Silliman, head of short-term rates trading at TD Securities in New York. The three month U.S. dollar Libor rate increased to 28.41 basis points on Wednesday, the highest since March 1, and up from 28.01 basis points on Monday. Some of this increase may be market driven and due to the selloff in Eurodollar futures on Monday and Tuesday, rather than based on fundamental factors, Silliman said.