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

Thus far in August, the intensity of Russian strikes on Ukraine appear to have eased. The first 11 days of this month have seen Moscow launch a daily average of 74 drones and one missile into Ukraine, compared with record-breaking July figures of 201 drones and around six missiles per day.

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.