Washington (AP) -- The Federal Reserve on Monday fined Switzerland's largest bank, UBS AG, $100 million for allegedly sending dollars to Cuba, Libya, Iran and Yugoslavia in violation of U.S. sanctions against those countries.

UBS operated a trading center for dollars in its Zurich headquarters under contract with the Federal Reserve of New York, to help the circulation of new U.S. notes and the retirement of old ones. One condition was that the Swiss bank not deliver or accept dollar notes through the depot to or from banks in countries that are under U.S. trade sanctions.

In an announcement, the Fed said that UBS had violated the agreement and that some former bank officers and employees, whom it did not name, concealed the transactions by falsifying UBS' monthly reports.