A professor who penned an op-ed in the Washington Post arguing for the Obama administration's $400 million payment to Iran did not disclose his ties to a group that paid experts to advocate for the Iran nuclear deal in the public sphere, the Washington Free Beacon reported Tuesday.

Allen S. Weiner, a Stanford law professor and contributor to the Post's opinions section, co-authored a piece arguing in favor of the Obama administration's decision to pay Iran $400 million in hard currency in what many described as a "ransom payment" for the release of several U.S. hostages. Weiner and the Post failed to disclose that the writer has long been on the payroll of the Ploughshares Fund, an organization recently exposed as a key cog in a White House-orchestrated campaign to build what it called a pro-Iran "echo chamber." ... Weiner, who serves as director of the Stanford Program in International and Comparative Law and co-director of its Center on International Conflict and Negotiation, has benefited from Plougshares funding since at least 2007, according to information obtained by the Free Beacon. Plougshares provided an undisclosed amount of funding for a 2007 paper Weiner authored about United Nations regulations governing weapons proliferation. Weiner and his co-authors praised the group for its support, according to a copy of the paper. In 2015, Ploughshares gave $100,000 to Stanford's Center for International Security and Cooperation, where Weiner acts as a senior lecturer, funding documents show. ... Weiner defended himself against accusations of impropriety, telling the Free Beacon on Tuesday that he did not write the piece at Ploughshares' request and did not coordinate or speak with anyone at the organization about the piece. "I have never spoken to anyone at Ploughshares about the Iran nuclear deal; indeed, until receiving your e-mail I had no idea what position, if any, Ploughshares had on the Iran nuclear deal," Weiner said. He went on to admit that he had "contact with Ploughshares" when the group contributed around $15,000 to the 2007 paper. "I did not receive those funds personally; the funds were contributed to Stanford University for a research project on which I was the principal investigator," Weiner explained, adding that he has also received funding in the past from the Foundation for the Defense of Democracies, a group critical of the nuclear deal.

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