Volodimir Zelenski said negotiators discussing a US-brokered peace initiative remain divided over territorial concessions, while Donald Trump expressed frustration with the way Kiev is handling the deal.

Zelensky said in a phone interview with Bloomberg that certain elements of the U.S. plan require further discussion on several “sensitive issues,” including security guarantees for the war-ravaged country and control of the eastern regions.

The Ukrainian leader stated that the talks have yet to reach an agreement on Ukraine’s Donbas, specifically the Donetsk and Luhansk provinces. “There are the perspectives of the US, Russia, and Ukraine – and we don’t have a single view on Donbass,” Zelensky said.

He stressed that Kiev is pushing for a separate agreement on security guarantees from Western allies, mainly the US.

Zelensky spoke after Trump criticized him – in contrast to comments in recent days about Putin’s reaction to the proposal – saying he was “a little disappointed that President Zelensky has not yet read the proposal.”

“There is one question that I – and all Ukrainians – want to get an answer to: if Russia starts the war again, what will our partners do,” Zelensky said. The Ukrainian leader was on his way to London when he made the remarks, where he will meet with Prime Minister Kir Starmer, German Chancellor Friedrich Murch and French President Emmanuel Macron to discuss the U.S. proposal.