Concerns have mounted in Europe and Ukraine that Kyiv may be pressed to give up land or accept other curbs on its sovereignty.

The Kremlin leader believes time is on his side as the exhausted and outgunned Ukrainian forces are struggling to stem Russian advances.

Trump and Putin will meet in Alaska on Friday to try to resolve the three-year war but the EU has insisted that Kyiv and European powers should be part of any deal to end the conflict.