Unintended consequences of Russian invasions

[RitterSport]

I don’t think we guaranteed their security, just that we wouldn’t invade or otherwise threaten their sovereignty. We discussed it here a little:

Ukraine Nuclear Agreement

What was the agreement that Western countries and Russia came to in exchange for Ukraine giving up their nukes? I’ve seen a range on this site and elsewhere that we (US, Europe, Russia) agreed just to leave their sovereignty intact, all the way to something more active about helping them defend themselves if someone threatens their sovereignty, like some sort of security agreement. What’s the FQ answer?

Russia made the same agreement, of course.