Trump warns Zelensky not to back off minerals deal

US President Donald Trump warned on Sunday that his Ukrainian counterpart Volodymyr Zelensky would have "big problems" if he goes cold on a deal to sign over mineral rights.

Trump is trying to broker a ceasefire between Ukraine and Russia, and has been pushing Zelensky to sign an agreement to give US firms access to Ukrainian rare earth mineral.

Briefing reporters on his Air Force Once jet, Trump said: "I see he's trying to back out of the rare earth deal. And if he does that he's got some problems. Big, big problems."