Excessive alcohol consumption has been the cause of many deaths among Russian forces in Ukraine, the British Defence Ministry said Sunday in its regular update on the war.

"While Russia has suffered up to 200,000 casualties since its full-scale invasion of Ukraine, a significant minority of these have been due to non-combat causes," it said.

It noted a recent Russian Telegram news channel report of "extremely high" numbers of incidents, crimes and deaths linked to alcohol consumption amongst the Russian forces.

"However, with heavy drinking pervasive across much of Russian society, it has long been seen as a tacitly accepted part of military life, even on combat operations," the report said.

The ministry listed other leading causes of non-combat casualties as poor weapons handling, road accidents and hypothermia. Russian commanders likely identify pervasive alcohol abuse as particularly detrimental to combat effectiveness, it said.

The ministry has put out daily updates since the start of the invasion based on information from its intelligence services. Moscow sees the reports as disinformation.