Generally speaking the IRS has disallowed a charitable deduction for contributions that are made to all Foreign Organizations.
However, there are some exceptions to the general rule in that some Foreign Charities that are allowed a deduction. The IRS has specifically allowed a charitable deduction to the following foreign charities as follows;
a. A U.S. organization that transfers funds to a charitable foreign organization if the U.S. organization controls the use of the funds or if the foreign organization is only an administrative arm of the U.S. organization, or
b.Certain Canadian, Israeli, or Mexican charitable organizations.
These charities in Israel, Mexico and Canada are a qualified foreign organization due to the existence of a "reciprocal treaty" with these governments.
For More discussion on this topic please refer to the following link below. Publication 526 (2007), Charitable Contributions