President Trump slapped sanctions on Turkey and called for an immediate ceasefire Monday, in a belated attempt to stem the carnage unleashed by his withdrawal of U.S. troops from northern Syria.

In an executive order signed Monday, Trump declared that Turkey's offensive "undermines the campaign to defeat the Islamic State of Iraq and Syria, or ISIS, endangers civilians, and further threatens to undermine the peace, security, and stability in the region.”

The move raises tariffs on Turkish steel from 25 to 50 percent, places sanctions on key Turkish officials and ministries, and freezes negotiations in a $100 billion trade deal with Ankara. "I am fully prepared to swiftly destroy Turkey's economy if Turkish leaders continue down this dangerous and destructive path," read the order.

Vice President Mike Pence said that during a phone call with Turkish President Recep Tayyip Erdogan Monday, Trump had also demanded an immediate end to the Turkish assault on Kurdish forces in northern Syria.

“The United States of America simply is not going to tolerate Turkey’s invasion in Syria any further. We are calling on Turkey to stand down, end the violence, and come to the negotiating table,” Pence told reporters, adding that he and national security adviser Robert O’Brien would be heading to Turkey in the “immediate future” to persuade Erdogan to stop the offensive.

Trump has faced blistering criticism at home and abroad for effectively greenlighting Erdogan’s long-threatened offensive by withdrawing U.S. troops from the border region, abandoning key partners the Kurds in the process.

Since Turkey invaded last week, more than 70 civilians, 135 Kurdish-led fighters, and 122 pro-Turkish fighters have been killed, along with eight Turkish soldiers, according to the British-based monitoring group the Syrian Observatory for Human Rights.

The fighting has driven more than 160,000 people from their homes, sparking fears of a looming humanitarian crisis, and forced the Kurds to seek help from the Syrian regime, whose forces have swept into the north to challenge the Turkish invasion.

But despite Trump’s new action against Turkey, which comes after days of appearing to simply acquiesce to the invasion, the president made clear he wasn’t planning to backtrack on his decision to pull troops out of the region.

“As I have said, I am withdrawing the remaining United States service members from northeast Syria,” he said Monday. The troops would remain in the region, with a “small footprint” of U.S. forces to remain at Tanf Garrison in southern Syria to continue the fight against ISIS.

U.S. lawmakers, furious about Trump’s precipitous withdrawal, are moving to impose sanctions of their own. Senate Majority Leader Mitch McConnell (R-Ky.) blasted the troop pullout Monday, saying that “abandoning this fight now and withdrawing U.S. forces from Syria would re-create the very conditions that we have worked hard to destroy and invite the resurgence of ISIS.”

On Tuesday, Erdogan, who has shrugged moves by European nations to pressure him to abandon the offensive, vowed in a televised speech that he would continue until his objectives are achieved. He plans to drive Kurdish fighters, which he considers indistinguishable from Kurdish separatists in southern Turkey, away from the border region, then repopulate the area with about 2 million Syrian refugees.

"God willing, we will quickly secure the region stretching from Manbij to our border with Iraq and ensure that, in the first stage, 1 million, and then 2 million Syrian refugees return to their homes on their own free will,” he said.

Britain announced Tuesday it was suspending arms exports to Turkey, following similar moves elsewhere in Europe. EU member-states pledged to suspend arms exports to Turkey Monday, prompting Turkey to respond that it would reconsider its cooperation with the bloc in light of its “unlawful and biased” approach.

Also on Tuesday, the U.N.’s human rights office called on Turkey to investigate alleged war crimes being carried out by its proxy militias, following the emergence of footage that appeared to show summary executions of Kurds. “Turkey could be deemed as a state responsible for violations by their affiliated groups,” spokesman Rupert Colville said.