The yen may strengthen past 100 to the dollar this year because there is "no quick fix" for the credit-market turmoil in the United States, former currency official Eisuke Sakakibara said on Friday.

The yen may also rise to 130 per euro, Sakakibara forecast, as traders pare carry trades, in which higher-yielding assets overseas are funded with Japan's currency. Treasury Secretary Henry Paulson and Federal Reserve Chairman Ben S. Bernanke's plans for an agency to buy bad debt from U.S. banks won't calm financial markets for another two years, he said.

"We could see more unwinding of yen carry trades because there is no quick fix," Sakakibara said in an interview Friday. "There could be appreciation of the yen, particularly against currencies like the Australian dollar and the euro. A stronger yen could be beneficial for Japan."