President Volodymyr Zelensky said Wednesday he had discussed a ceasefire in Ukraine with US leader Donald Trump on the sidelines of NATO's summit in The Hague.

Zelensky said on social media that the meeting was "long and substantive" adding: "We discussed how to achieve a ceasefire and a real peace. We spoke about how to protect our people."

A source in the Ukrainian presidency told AFP Zelensky was "satisfied with the conversation and grateful to Trump." The Ukrainian leader's office said separately the meeting had lasted around 50 minutes.