The presidents of Russia and Ukraine have separately held telephone talks with US President Donald Trump to discuss the situation in Ukraine, ahead of NATO’s upcoming summit.

An aide to Russian President Vladimir Putin said on Saturday that Putin congratulated Trump and the American people on the 250th anniversary of their country’s independence.

Yury Ushakov also said Putin told the US president that Russian forces are advancing “confidently” in Ukraine.

Ushakov added that Trump reaffirmed his readiness to facilitate an early end to the fighting, and said his special envoy Steve Witkoff and son-in-law Jared Kushner stand ready to visit Moscow at a mutually convenient time.

Ushakov said the conversation between the two leaders lasted nearly 90 minutes.

Also on Saturday, Ukrainian President Volodymyr Zelenskyy posted on social media that he spoke with Trump and congratulated him on the US independence anniversary.

Zelenskyy also wrote, “There is a real prospect to put an end to this war,” adding that he and Trump agreed to continue discussions.

The telephone conversations took place ahead of a NATO summit in Turkey that will start on Tuesday. Support for Ukraine is on the meeting’s agenda.

Putin and Zelenskyy are both believed to be attempting to demonstrate their personal closeness with Trump and gain his support.