He can support his European allies, including, for example, Nato, the EU, Germany, France, Britain and Ireland.
He appears to especially value his Irish roots. He has already made it crystal clear that there will not be an agreement with UK if UK damages Ireland.
There is no reason to suppose he will support the actions of a country that seeks to disadvantage Ireland, nor a country that signs an international agreement and then declares its intention to break it, and to break international law.
Unlike our own Great Leader, he is a mature, intelligent and experienced statesman and will probably not bear much of a grudge against Boris for foolishly insulting Obama and Hilary Clinton. No reason to suppose it will help, though.