ADVERTISEMENT "This was a decision by the administration which had the clearly observable result that we're seeing. To have the vice president and the secretary of State going to meet with Erdoğan and suggesting that somehow we're surprised by what's happening is disingenuous," Romney told reporters on Wednesday.

"Very clearly it was a decision by the administration that which has led to what you're seeing. This is a bit like the farmer locking the barn door after the horse has left," he continued.

Turkey's military operation came after the White House announced that it was pulling back U.S. troops in northern Syria.

Trump has faced fierce criticism from Republicans, including Romney, over the strategy, which lawmakers have warned will embolden the ISIS and harm the Kurds, who worked with the United States to fight ISIS.

Romney reiterated on Wednesday that the "decision was a bad one."

Trump has sent mixed signals about his decision, slapping new sanctions on Turkey even as he's publicly distanced himself from the Kurdish fighters.

During a White House meeting on Wednesday, Trump told reporters that the Kurds "were no angels."

Asked about Trump's comments on Wednesday, Romney added: "Oh my goodness gracious. Oh my goodness gracious. The Kurds are our friends and our allies."

"Abandoning them is was a very dark moment in American history. Let me note, the president could have negotiated with Erdoğan to say alright you have concerns. We understand those. ... Now we're acting like this is a big surprise that the Turks are doing what they're doing," he added.

Lawmakers are weighing how to respond to Trump's decision to pull back troops and Turkey's invasion of northern Syria. The House is expected to vote on Wednesday on a resolution that will formally break with Trump's strategy and urge Turkey to end its military operation.

Multiple lawmakers are also floating additional sanctions against Turkey.

"You know, I think it's appropriate to apply sanctions when you see a nation wipe out our friends," Romney said when asked about the sanctions. " ...[But] the door was opened for what is occurring by the decision taken by the administration. So for us to be shocked and to look at Turkey and say 'my goodness we can't believe what you're doing,' we were the ones who opened that door."