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BUENOS AIRES, May 18 (Reuters) - Argentina's peso weakened 1.12 percent to 24.61 per U.S. dollar on Friday amid a regional currency selloff while the central bank offered to sell up to $5 billion in the foreign exchange market at 25 to the greenback, traders said.
The bank made the same offer on Wednesday and Thursday but it did not intervene as the peso remained stronger than 25 per dollar. Those were the first trading sessions since May 9 in which the bank did not sell reserves to prop up the peso, which has weakened more than 17 percent this month.
Argentina was especially hard hit by a general flight from emerging markets in recent weeks. The currencies of neighboring Brazil, Chile and other Latin American countries were also weaker on Friday while Argentina's Merval stock index extended an eight-day rally by rising 0.65 percent.
Reporting by Jorge Otaola and Walter Bianchi, writing by Hugh Bronstein; Editing by Bernadette Baum and Susan Thomas