Signatories also call on the government in Tehran to stop the move and lift social restrictions against Afghans living in Iran.
The statement describes the forced repatriation of Afghans to a country that is still suffering from more than two decades of conflict as an "inhumane and unacceptable" policy.
Afghan authorities recently urged Iran to stop the repatriation of Afghan refugees, saying that they cannot afford to resettle them.
RFE/RL Afghanistan Report
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