US President Donald Trump said on Tuesday that Washington will lift sanctions imposed on Turkey over its purchase of Russia's S-400 missile defence system, a move that could help Ankara rejoin the F-35 fighter jet programme.

Speaking after talks with Turkish President Recep Tayyip Erdogan in Ankara during the NATO summit, Trump said Cabinet officials were working on removing the sanctions under the Countering America's Adversaries Through Sanctions Act. He also said selling F-35 jets to Turkey was "certainly something we will consider." Turkey was removed from the programme in 2019 after buying the Russian system.

NATO chief faces fresh test as Trump demands allies' loyalty ahead of Turkey summit

Trump and Erdogan highlighted their close relationship, with Trump praising Turkey's support for the US, particularly during the Iran conflict. He said he attended the NATO summit partly because of his ties with Erdogan.

Earlier, NATO announced several multinational defence projects worth billions of dollars, including a deal for Swedish company Saab to supply up to 10 GlobalEye surveillance aircraft to replace the alliance's ageing AWACS fleet. NATO Secretary-General Mark Rutte called the investments "money well spent" and said more contracts would strengthen the alliance's military capabilities.

The alliance also announced plans to buy Airbus refuelling and transport aircraft and up to five Triton surveillance drones. While no financial figures were disclosed, some projects will be supported by a European Union defence loan programme worth up to $170 billion.

Trump again pressed NATO allies to boost defence spending, while Pentagon officials promoted a "NATO 3.0" vision under which European members would shoulder greater defence responsibilities.

The summit also featured renewed debate over Turkey's possible return to the F-35 programme. Israeli Prime Minister Benjamin Netanyahu urged Washington not to approve the sale, arguing it could alter the Middle East's military balance.

Separately, Ukrainian President Volodymyr Zelenskyy renewed his call for NATO membership, saying Ukraine's battle-tested military would strengthen the alliance as concerns grow over possible Russian hybrid attacks against Europe.