Russian and Turkish state sources confirmed Wednesday that deliveries of S-400 anti-aircraft missile systems are now underway, with parts for the advanced Russian systems already having arrived in Turkey via transport planes with a team of Russian specialists, reportedly in the eastern Anatolian city of Malatya as well as the capital of Ankara.

Russian Presidential Spokesman Dmitry Peskov announced of the provocative transfer which has for the past year been met with condemnation by the United States - including the threat of sanctions and blockage of F-35s to Turkey - that “Deliveries of Russian S-400 complexes to Turkey are carried out as planned.”

Image source: AFP

The US this week again warned of “real and negative” consequences if Turkey completes the purchase of the S-400, which is now definitively a done deal with the S-400 equipment arrivals in Turkey. “Those consequences include participation in the F-35 program,” a State Department spokesperson said Tuesday.

Turkey, for its part, shot back on Wednesday that the US must avoid taking the “wrong steps,” with the foreign ministry saying in a statement, “We are inviting the US to avoid taking the wrong steps which would exclude diplomacy and dialogue and harm relations.”

Starting months ago Turkey consistently affirmed it's "a done deal" and that there would be no cancellation, even as Washington urged "alternatives" such as US Patriot missiles.

But as of today it now appears there's no further dialogue to be had on the S-400, which early this week President Recep Tayyip Erdogan declared would be a positive development for the defense of the region "and for the world". On Wednesday Erdogan further described to reporters:

"Some people have a question about why we buy the S-400, why we make such an investment. If we have to, we will have the right to use them. If someone attacks us, we will use these air defense systems. That's why we make such an investment.”

Interestingly, the new US Ambassador to Turkey, David Satterfield, just arrived in the country to take up his post at the US Embassy in Ankara on same day the S-400 deliveries began.

The State Department's stance is that "nothing has changed" concerning US resistance to the S-400 deal. Concerns have been driven over fears that it would allow Russia to access sensitive information on the defenses of NATO aircraft, especially if Turkey's military is simultaneously operating the Lockheed Martin made F-35 advanced stealth fighter.

“The Turkish authorities know the legislation that has been passed in Congress as it relates to CAATSA,” U.S. State Department spokeswoman Morgan Ortagus said on Tuesday . “We have said that Turkey will face real and negative consequences if they accept the S-400, including participation in the F-35 program.”

At least two batches of the S-400 surface-to-air missile batteries are expected to be delivered in total, however, they likely won't be ready for deployment until October, according to reports.

The question of which side decides to blink or compromise first will be interesting, given we're now past the point of no return.