The tax imposed by section 2001 shall be credited with the amount of any estate, inheritance, legacy, or succession taxes actually paid to any foreign country in respect of any property situated within such foreign country and included in the gross estate (not including any such taxes paid with respect to the estate of a person other than the decedent). The determination of the country within which property is situated shall be made in accordance with the rules applicable under subchapter B (sec. 2101 and following) in determining whether property is situated within or without the United States.
In any case where a deduction is allowed under section 2053(d) for an estate, succession, legacy, or inheritance tax imposed by and actually paid to any foreign country upon a transfer by the decedent for public, charitable, or religious uses described in section 2055, the property described in subparagraphs (A), (B), and (C) of paragraphs (1) and (2) of subsection (b) of this section shall not include any property in respect of which such deduction is allowed under section 2053(d).
For purposes of the credits authorized by this section, each possession of the United States shall be deemed to be a foreign country.