A key exclusion clause in war risk marine insurance policies is being closely scrutinised as the world’s major powers line up on opposite sides amid the growing Russian military activity around Ukraine.

The clause involves the so-called ‘major powers’ exclusion clause which would withdraw cover if any of the world’s leading countries entered some sort of conflict with each other, the nature of which is not clearly defined.

The clause has been in place since 1949 and is in the terms and conditions of all the leading insurance policies including the UK, Nordic and Hellenic war risk plans.