Except as otherwise provided by treaty or this title, whenever compensation is payable to a beneficiary who is an alien not residing in the United States, the department or self-insurer, as the case may be, shall pay the compensation to which a resident beneficiary is entitled under this title. But if a nonresident alien beneficiary is a citizen of a government having a compensation law which excludes citizens of the United States, either resident or nonresident, from partaking of the benefit of such law in as favorable a degree as herein extended to nonresident aliens, he or she shall receive no compensation. No payment shall be made to any beneficiary residing in any country with which the United States does not maintain diplomatic relations when such payment is due.