Beto O’Rourke referred to Israeli Prime Minister Benjamin Netanyahu as a “racist” on Sunday, accusing him of standing in the way of any chance of peace in the Middle East.

While campaigning at the University of Iowa, the Democratic presidential candidate said Netanyahu has “joined forces with far-right parties who are inherently racist in their speech and the way that they want to treat their fellow human beings in that part of the world.”

He later told reporters Netanyahu is a “racist.”

“The U.S.-Israel relationship is one of the most important relationships that we have on the planet, and that relationship, if it is to be successful, must transcend partisanship in the United States, and it must be able to transcend a prime minister who is racist as he warns about Arabs coming to the polls, who wants to defy any prospect for peace as he threatens to annex the West Bank, and who has sided with a far-right racist party in order to maintain his hold on power,” said O’Rourke, a former Texas congressman who lost his campaign to unseat Republican senator Ted Cruz last year.

He continued, “I don’t think Benjamin Netanyahu represents the true will of the Israeli people.”

Netanyahu vowed Saturday to annex Israeli settlements in the occupied West Bank if he wins another term in his country's election Tuesday. O’Rourke said such a move “will make peace in the long term impossible.”

O’Rourke also criticized Palestinian Authority President Mahmoud Abbas for his “inability to bring his side to the table to negotiate in good faith” and accused him of “not been faithful in pursuing peace.”

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