President Donald Trump on Monday signed an executive order to impose sanctions and visa bans on top members of the Turkish government as punishment for a Turkish offensive into Syria that Trump personally gave a green light to earlier this month.

The US will place sanctions on three of Turkeys most powerful officials the ministers of defense, energy and interior and its departments of defense and energy, Treasury Secretary Steve Mnuchin said Monday.

To avoid suffering further sanctions imposed under this new executive order, Turkey must immediately cease its unilateral offensive in northeast Syria and return to a dialogue with the United States on security in northeast Syria, Secretary of State Mike Pompeo said in a statement.

Trump broke with his previous narrative of a withdrawal from Syria to end never-ending war and said that a garrison of US troops will remain in the country at the At-Tanf outpost. He will also subject Turkish steel to increased tariffs, he added.

The Turkish military and allied militias since Wednesday have been attacking a Kurdish-controlled enclave in northern Syria that Turkish President Recep Tayyip Erdogan says poses a threat to his countrys security. The US has closely worked with the dominant Kurdish militia in the region, known as the YPG, since 2014 in its fight against the Islamic State. But that policy has long been controversial, especially with the Turks, because the YPG has historic ties to the PKK, a Kurdish group that has fought the Turkish state since 1984 and that the US considers a terrorist organisation.

World powers, US lawmakers and rights groups have roundly condemned the Turkish move following Trumps support, noting that it threatens an effective partner against ISIS and could result in major human rights abuses against the more than 2 million people living in the Kurd-controlled area. Experts have also warned that the fighting could empower remnants of ISIS who have been held in camps that the Kurds could be forced to leave undefended. And the US abandonment of the Kurds could bolster Syrias brutal Assad regime, which the YPG has now turned to for help.

The Trump administrations goal is a ceasefire, a senior administration official said in a call Monday with reporters after the announcement. The administration wants the various forces on the ground to hold in place and to then come forward with a set of plans to resolve the underlying reasons why Turkey went in and to meet Turkeys security needs, its legitimate security needs.

The president is deeply committed to ending the unnecessary violence, another senior administration official said on the call, noting that the US was monitoring violence against religious minority groups and other potential abuses.

That message is in contrast to the presidents narrative about the episode on Twitter, where he first revealed his plans for sanctions. For days, he has been suggesting the Turks and Kurds are bound to violently clash and its not Americas responsibility to intervene.

Vice President Mike Pence will soon be traveling to Turkey, and top Trump aides will be working on the bid for a ceasefire, officials said.

Trumps move is unlikely to immediately halt the Turkish offensive. The Treasury and State Departments will have further work to do to sanction less-powerful individuals who might be more vulnerable to pressure, and they will likely be careful to avoid key figures in Turkish politics or the military with whom the US is likely to interact in the future, given Turkeys continued membership of the NATO alliance.

American sanctions also have relatively limited effect on Turkey because the country is far more economically reliant on the European Union, which has yet to say it will also implement sanctions over Syria and is traditionally more cautious than Washington in its dealings with Ankara.

And it will probably take more than this to change Erdogans calculus. The Turkish leader is convinced that moving against the Kurds is important for his political support at home, given the widespread view among Turks including many of those opposed to Erdogan that the Syrian Kurds are a threat like the PKK. Ankara has been defiant in defending and continuing its operation even as global criticism has grown.

One Trump aide acknowledged the importance of the effort to Erdogan in the call. Erdogan was going to act regardless of what we did, the official said in response to a question about Trumps responsibility for what members of his own party are calling a strategic disaster.

The administrations clarity on that point makes it hard to understand why it thinks it can now force an about-face.

A change from Erdogan isnt expected because the messages coming from the Trump administration have been so mixed, said Merve Tahiroglu, the Turkey program coordinator at the Project on Middle East Democracy.

Trump has sanctioned Turkey before, but he does this in such a transactional way that the message is, I will sanction you now but you just have to give me one concession and I will lift it, she added, noting the administrations temporary penalties on Erdogan over Turkeys jailing of American pastor Andrew Brunson.

Greater financial sanctions could cause some pain in Turkey because of the countrys economic downturn.

But the tight personal bond that Turkeys autocratic president has forged with Trump will probably make him confident he can ultimately have his way and can use the squabbling in Washington over Trumps flip-flops to his advantage to reduce popular concern over the effects of the sanctions, Tahiroglu said. These steps are really not resonating in Ankara.... Erdogan is presenting Turkey to the Turkish people as collateral damage in this intra-American or intra-Republican struggle.

As the fighting continues, the implications of Turkeys and Trumps approach only get darker. Asked about reports of ISIS detainees escaping, a senior administration official said, I cannot corroborate who may have broken out of the prisons at this point.

This article has been updated with further details about the situation in Turkey and Syria.