Although current earned income can be excluded from U.S. tax if you're living abroad, retirement income cannot. IRA distributions are taxable and in addition, IRS requires that U.S. tax be withheld from distributions going to addresses outside the U.S. No current RMDs are due from the owner of a Roth IRA - the usual rules apply if distibutions are taken from the Roth. No tax on removing contribution or conversion amounts but earnings could be taxable in the first 5 years the Roth is in place.
