WASHINGTON, July 23 (Reuters) - The U.S. Trade Representative’s office on Friday said it had determined that no tariff action against Vietnam was warranted after the country’s central bank agreed with the U.S. Treasury not to manipulate its currency for an export advantage. In a statement, USTR said it found that the U.S. Treasury-State Bank of Vietnam agreement earlier this week “provides a satisfactory resolution of the matter subject to investigation and accordingly that no trade action is warranted at this time.” (Reporting by David Lawder; Editing by Leslie Adler) Our Standards: The Thomson Reuters Trust Principles.