July 31 (Reuters) - The US Treasury has informed a number of banks that it may intervene in the yen market on Friday and that they should "stand ready for future action," a source familiar with the matter told Reuters.
The notice to banks, channeled through the Federal Reserve Bank of New York, comes a day after Japanese authorities stepped in to prop up the yen, setting the currency up for its biggest weekly rise since February, pulling it off of four-decade lows against the dollar.