The incident in question relates to Gibraltar, Gibraltar is part of the EU and EU law does apply there.
Yes but the tanker didn't break EU law because it doesn't belong to a member state so the sanctions don't apply to it. If it was a German tanker than the sanctions would apply and it would have broken the law, that's how it works.
To put this in perspective, if they wanted to the Russians could load a tanker with oil in Kaliningrad, then sail it around Germany, France, Spain, Portugal, etc all the time blaring over a loudspeaker that it's carrying oil to Syria to be refined. And they would do nothing about it because it's not breaking any laws as the Syrian sanctions do not apply to it, hence why they refused to stop the Iranian tanker and Trump had to call up the 51st state.
LOL what?
So just to get this straight, because a civilian ship is owned by a non-EU member then when it is in UK or EU waters then UK or EU laws don't apply to it?
No, EU
sanctions do not apply to it, you break the law by violating the sanctions, if the sanctions do not apply to you then there's nothing to violate.
Here, I'll make it super simple:
EU member: Yes
Complying with EU sanctions: Yes
Breaking EU law: No
EU member: Yes
Complying with EU sanctions: No
Breaking EU law: Yes
EU member: No
Complying with EU sanctions: Yes/No
Breaking EU law: No