Not going to happen, it's better to supply Ukraine with enough material so they can actually win, Russia isn't going to negotiate anything when it thinks it can gain more by continuing.
In the end there will have to be peace negotiations, but currently this puts Ukraine on the back foot as Russia still occupies quite a lot of territory.
In my view, Ukraine would really need to push Russia further back before seeking peace, for that they need ammo and weaponry.
P.S. EU/NATO threatening to join in won't go down well unless we're willing to entertain the possibility Russia would counter by threatening nukes, that is a big test of resolve. It's clear the supply of weapons and ammo to Ukraine hasn't caused this card to be played, but intervention into the conflict more directly may have consequences.