Turkish President Recep Tayyip Erdogan has revealed that the first delivery of the Russian S-400 missile defense system would take place within 10 days, after saying there would be no US sanctions over the deal. Turkey and the United States, NATO allies, have been at odds over Ankaras decision to purchase the S-400s, with Washington warning of US sanctions if the delivery took place. Turkey has dismissed the warnings, saying it would not back down. "Within 10 days, maybe within one week, the first shipment will have arrived. I told Trump this openly," Erdogan was cited as saying by Hurriyet newspaper after a meeting with US President Donald Trump. The United States says the S-400s will compromise its Lockheed Martin Corp F-35 fighter jets, of which Turkey is a producer and buyer. Washington has also formally started the process of expelling Turkey from the F-35 program, halting the training of Turkish pilots in the United States. But on Saturday, Erdogan said Trump had told him there would be no sanctions over the Russian deal, after Trump said Turkey had been treated unfairly over the move. Following the talks, the White House said Trump "expressed concern" over the S-400 deal and "encouraged Turkey to work with the United States on defense cooperation in a way that strengthens the NATO alliance." Speaking to reporters after the G20 summit in Japan, where he held bilateral talks with Trump, Erdogan said he believed the dispute over the S-400s would be overcome "without a problem" and added that his US counterpart supported Turkey in the dispute. "In our phone calls, when we come together bilaterally, Mr Trump has not said so far: We will impose these sanctions. On the S-400s, he said to me: You are right. We carried this issue to a very advanced level," Erdogan said, according to broadcaster NTV. "At this advanced level, Trump said: This is injustice. This is very important. I believe that we will overcome this process without any problems," Erdogan added.