If your American client is considering renouncing his U.S. citizenship, warn him he might never be granted re-entry in the country if he completes the process, says Moody’s.

It adds, “Senators Jack Reed and Chuck Schumer [recently] filed an amendment to the immigration reform bill. If it passes, this amendment would exclude from re-entry not only former citizens who renounce for tax avoidance purposes, but also individuals who are considered “Covered Expatriatesunder Internal Revenue Code Section 877A.”