Russia's Rostec state conglomerate had said earlier that Russia and Turkey are in talks about the possibility of jointly manufacturing some components of Russia's S-400 missile defence system in Turkey.
President Tayyip Erdogan said on Friday Turkey would turn elsewhere for fighter jets if the United States will not sell it F-35s, adding that the US decision to cut Ankara from the jet production programme would not deter it from meeting its needs.
The United States said last week it was removing NATO ally Turkey from the F-35 programme, as it long threatened after Ankara purchased and received delivery of Russian S-400 missile defences. US President Donald Trump has yet to decide on sanctions on Turkey that appear to be required by US law.
Erdogan, speaking publicly about Ankara's strained ties with Washington for the first time in 11 days, said he hoped US officials would be "reasonable" on the question of sanctions.
The head of Russia's Rostec state conglomerate had said earlier that Russia and Turkey are in talks about the possibility of jointly manufacturing some components of Russia's S-400 missile defence system in Turkey, the TASS news agency cited Sergei Chemezov.
After the Pentagon announcement, Turkey's foreign ministry said in a statement: "We invite the United States to return from this mistake which would open irreparable wounds in strategic relations."
NATO secretary general Jens Stoltenberg, speaking at the Aspen Institute's annual security forum in Aspen, Colorado, said he was concerned at Turkey's expulsion from the F-35 programme.
"The S-400, the Russian air defence system, it’s not possible to integrate into the integrated NATO air defence and missile system, which is about sharing, you know, radar picture, about joint air policing, which is about shared capabilities. And Turkey has not asked for that," Stoltenberg said.
The S-400 acquisition is one of several issues that have frayed ties between the two allies, including a dispute over strategy in Syria east of the Euphrates River, where the United States is allied with Kurdish forces that Turkey views as foes.
The Pentagon had already laid out a plan to remove Turkey from the programme, which included halting training for Turkish pilots on the aircraft.