A year and a half later Turkey acquired a Russian missile defense system, violating US sanctions law, president Donald trump implemented sanctions against the NATO ally.

Its refusal to apply these sanctions had sparked bipartisan ire in Congress, but allowing them has now enraged Turkey, including Turkish President Recep Tayyip Erdogan, amid the deterioration of relations between it and its Western allies like the United States. United.

The sanctions, announced by the US Treasury on Monday, targeted Turkey’s defense procurement agency, known as the Presidency of Defense Industries, and its senior officials, including its chairman.

Congress was set to force Trump’s hand, passing his annual defense policy bill last week that required the White House to implement those sanctions within 30 days – although a senior official of the State Department denied that it had any impact on Trump’s decision.

Turkey acquired the missile defense system, known as the S-400, in July 2019. The purchase violated a sweeping sanctions law passed in the summer of 2017 by wide margins in the House and Senate for force Trump to be tougher on Russia. Trump, who wanted to avoid an embarrassing waiver of the veto, reluctantly signed the law.

The Countering America’s Adversaries Through Sanctions Act, or CAATSA, targeted Iran, North Korea and Russia – demanding sanctions against any country that made a “major purchase” of defense or intelligence equipment in Moscow.

“Today’s action sends a clear signal that the United States will fully implement Section 231 of CAATSA and will not tolerate significant transactions with Russia’s defense and intelligence sectors,” said Secretary of State Mike Pompeo in a statement.

“I also urge Turkey to immediately resolve the S-400 issue in coordination with the United States. Turkey is a valued ally and an important regional security partner for the United States, and we seek to continue our history. decades of productive defense, sectoral cooperation by removing as soon as possible the obstacle of Turkey’s possession of the S-400 “, he added.

Prior to today, the Trump administration had only used these sanctions once, penalizing the Chinese defense procurement agency for its own purchase of the S-400, as well as the Russian fighter jet. Sukhoi Su-35.

After Turkey acquired the same missile system, Trump excluded the country from the F-35 program, the most sophisticated stealth fighter in the United States, including its role in the production of the aircraft. At the time, the Pentagon said Turkey’s S400 would jeopardize the F-35s and undermine NATO’s ability to cooperate militarily – which Turkey has denied.

Since buying Turkey, Republicans have joined Democrats in urging Trump to go further and sanction Ankara, something the president, who called Erdogan a friend, refused to do. U.S. officials have previously said sanctions could be avoided if Turkey does not use the missile system, but Turkish officials tested it in October.

Senator James Risch, R-Idaho, chairman of the Senate Foreign Relations Committee, called Monday’s sanctions “a long time ago.”

In the face of this bipartisan pressure, Trump had repeatedly backed Erdogan by criticizing the Obama administration for refusing to sell Turkey the US Patriot missile defense system, which, according to Trump, forced Erdogan to turn to the United States instead. Russia.

“It’s a mess. It’s a mess, and honestly, it’s not really Erdogan’s fault,” Trump said in 2019 when Russia started shipping the S400. “I think he was treated unfairly.”

But that’s not true, with Turkey having had several opportunities to purchase Patriot missiles over the years, according to current and former US lawmakers and officials.

“Sadly, Turkey has rejected each of these efforts for literally several years now and many commitments and alternatives have been offered, ultimately leaving us no choice,” Trump’s top arms control diplomat said Assistant Secretary of State for International Security and Non-Proliferation Chris Ford said Monday.

Asked about reports that Trump had long opposed sanctions to avoid upsetting Erdogan, Ford declined to comment, telling reporters at a briefing that he was “unable to unbox alleged insider material or real of our deliberative process for you “.

Erdogan condemned the US move on Monday, saying: “We expect support from our NATO ally, the United States, in our fight against terrorist organizations and forces accountable to our region, not sanctions, ”according to CNN Turk.

The Turkish Foreign Ministry pledged to take “the necessary measures against this decision”, adding in its statement that Trump “has admitted on numerous occasions that the acquisition of Turkey is justified”.

Monday’s sanctions include a ban on all US export licenses for Turkey’s Defense Industries Presidency, also known as SSB, as well as an asset freeze and US visa ban for its President Ismail Demir and other senior officials.

“Any decision taken abroad towards me or our institution will not change my position and that of my team; it cannot in any way prevent the Turkish defense industry,” Demir said of the sanctions in a tweet. Monday.

In addition, SSB will be prohibited from receiving US export licenses, loans over $ 10 million from US banks, assistance from the US Import-Export Bank, and loans from international financial institutions such as the United States. World Bank.

Although higher Turkish officials were not also punished, Ford said targeting SSB was an “important step”, especially against a US ally. The delay between the purchase of Turkey and the US sanctions is “a sign of the caution with which we have tried to think through this in a way which will hopefully allow us to maintain a very good and constructive relationship with our ally, while sending the signal that there is a certain behavior that we cannot accept “, he added.

ABC News’ Engin Bas contributed to this report from Istanbul.