Regardless of what specific rules could be set you have to consider rules of engagement and potential escalation. What happens if a Russian merchant vessel (either legitimately flagged or shadow fleet) refuses to cooperate? Do you use force to stop them? What if they're being escorted by a Russian warship or combat aircraft?

▲

dzhiurgis an hour ago | parent [-]

You put mines and wait. We need to stop with “what if escalation” mantra when it was always Russians escalating.

	▲	nradov an hour ago \| parent [-]
		Put mines where? How do you prevent neutral vessels from hitting them? What happens when they inevitably break loose in a storm and drift away? Naval mines are quite effective for closing down a body of water in an unrestricted hot war but we haven't reached that stage yet. EU and NATO countries still want to be able to use the Baltic Sea and Gulf of Finland for their own purposes. You haven't really thought this plan through.