The most senior US general estimates that around 100,000 Russian and 100,000 Ukrainian soldiers have been killed or injured in the war in Ukraine.

Gen Mark Milley, chairman of the US Joint Chiefs of Staff, also suggested that around 40,000 civilians had died after being caught up in the conflict.

The estimates are the highest offered yet by a Western official. But he observed that signs Kyiv was willing to re-enter talks with Moscow offered "a window" for negotiations.

In recent days, Ukraine has signalled a willingness to hold some discussions with Moscow, after President Volodymyr Zelensky dropped a demand

President Volodymyr Zelensky dropped a demand that his opposite number, Vladimir Putin, must be removed from power before negotiations could resume.

Both Russia and Ukraine would have to reach a "mutual recognition" that a wartime victory "is maybe not achievable through military means, and therefore you need to turn to other means".

The scale of the casualties could convince both Moscow and Kyiv of the need to negotiate over the coming winter months, when fighting may slow due to freezing conditions.

"You're looking at well over 100,000 Russian soldiers killed and wounded," Gen Milley said. "Same thing probably on the Ukrainian side." Both Ukraine and Russia jealously guard their casualty numbers.