Ukrainian President Volodymyr Zelensky needs to return to the negotiating table and strike a deal on US access to Ukraine's critical minerals, White House national security adviser Mike Waltz has said.

National security adviser Mike Waltz says President Donald Trump’s increasingly tough criticism of Volodymyr Zelenskyy reflects the growing frustration with what is seen as his creating roadblocks to finding an endgame to Russia’s invasion of Ukraine.