Foreign earned income is not taxable compensation for IRA contribution purposes. If you have no other taxable compensation other than the foreign earned income you cannot contribute to an IRA.
See IRS Publication 590-A, Contributions to Individual Retirement Arrangements (IRAs) - https://www.irs.gov/publications/p590a#en_US_2016_publink1000230366
Go to this IRS website for IRA contributions - https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-ira-contribution-li...
