US President Donald Trump spoke with his Russian and Ukrainian counterparts Vladimir Putin and Volodymyr Zelensky Saturday to discuss the conflict in Ukraine ahead of a NATO summit in Ankara, the Kremlin and Zelensky said.

The calls were both to mark the 250th birthday of the United States, both sides said.

“The presidents naturally addressed the issue of a settlement in Ukraine, taking into account, in particular, Donald Trump’s upcoming participation in the NATO summit in Turkey on July 7 and 8,” said Yuri Ushakov, the Kremlin’s foreign policy aide, according to the RIA Novosti news agency.