US President Donald Trump has announced a "lengthy and highly productive" phone call with Russian President Vladimir Putin, during which they agreed to begin immediate negotiations to end the war in Ukraine.

The conversation, which Trump revealed on his social media platform, covered multiple topics and resulted in both leaders committing to start peace talks.

"We have also agreed to have our respective teams start negotiations immediately," Trump stated in his post.

Ukrainian President Volodymyr Zelensky said on Wednesday he spoke by phone with Trump and discussed "opportunities to achieve peace" and the preparation of a document governing security and economic cooperation.

During the call, Trump and Putin discussed a wide range of topics including Ukraine, the Middle East, energy, artificial intelligence and the power of the dollar.

Both leaders agreed on the urgent need to stop the bloodshed in Ukraine.

Trump said he believes progress is being made towards ending the conflict, though he has not detailed specific plans for achieving peace.

As part of their agreement, Trump and Putin committed to visiting each other's nations.

Trump has repeatedly emphasised his desire to swiftly end the conflict in Ukraine, which has claimed hundreds of thousands of lives.