WASHINGTON, June 6 (Reuters) - The U.S. Federal Reserve announced on Thursday it had terminated a 2013 enforcement action it imposed on JPMorgan Chase after the bank reported significant losses stemming from its "London Whale" trading scandal.

The regulator said it decided to end the enforcement action after the bank had made substantial improvements in its risk management and internal audit functions since the 2013 order.

The bank lost $6.2 billion on the contracts arranged by a London-based bank trader, which attracted attention and criticism from policymakers in Washington. (Reporting by Pete Schroeder Editing by Tom Brown)