The head of one of the groups that co-sponsored the Iran deal protest rally last week at the Capitol in Washington, D.C. told TPM that Republican presidential frontrunner Donald Trump’s stance on taking in Syrian refugees was “stupid.”

Trump was asked about the Syrian refugee crisis Tuesday night on Fox News’ “The O’Reilly Factor.” After the Republican presidential frontrunner noted that taking in refugees would pose a “security risk,” host Bill O’Reilly asked if he objected to the U.S. taking in migrants from the Middle East and North Africa.

“I hate the concept of it, but on a humanitarian basis, with what’s happening, you have to,” Trump responded.

Morton Klein, the president of the right-wing Zionist Organization of America, told TPM in a Thursday phone interview that it was “stupid” for Trump to open the door to America taking in Syrian refugees.

“It’s very stupid to communicate that position on Syrian refugees,” Klein said. “It’s stupid. And I never say that word.”

Klein said it was inconsistent for the real estate mogul to expound on the dangers of immigrants crossing the U.S.-Mexico border, yet be open to accepting refugees whose backgrounds, he said, could not be vetted and who are from a country “whose population has such antipathy towards the United States.”

“It’s especially surprising, especially shocking, that here’s the man who said ‘Let’s not bring in illegal Mexicans, allow that to happen, because so many of them are killers and rapists,'” he said. “Why would he be worried about Mexicans and not worried about Syrians? It just makes no sense.”

Trump spoke with O’Reilly the night before the anti-Iran deal rally. Klein said that he brought up the subject at the event but didn’t get a response from the real estate mogul. He added the caveat that Trump was surrounded by people and seemed not to know who Klein was.

But by the time CNN asked Trump about up the refugee crisis again following the Wednesday rally, the billionaire’s position on the issue started to get a little wishy-washy.

“I think we should help, but I think we should be very careful because frankly, we have very big problems,” he told CNN. “We’re not gonna have a country if we don’t start getting smart.”

Trump hardened his line on Syrian refugees even more in a Wednesday night interview with Fox News’ Sean Hannity.

“Russia’s not taking, nobody’s taking,” Trump said of the refugees. “We’re supposed to take? We have to straighten out our own problems.”

Another co-sponsor of the Iran deal protest rally, the anti-Muslim Center for Security Policy, did not respond to requests for comment from TPM.

Trump’s flip-flop was complete by Thursday night, when he told Fox News’ Greta Van Susteren that the Obama administration shouldn’t be planning to take in 10,000 Syrian refugees next year. He said it was a “terrific concept” to instead set up “safe zones” in that country for the refugees.

But The Guardian reported that during a Friday foreign policy conference in Ukraine, where Trump spoke via a glitchy video link, the billionaire praised Germany for taking in Syrian refugees before he again suggested setting up a “safe zone” somewhere in Syria. The video link apparently cut out before Trump could get any more specific.