I'm not an EU scholar, so don't take my word for it.
But as far as I can see, the EU's position is this:
The EU regrets Brexit which has caused a lot of harm and a lot of pain in the EU, too.
However, it will not want to see the UK rejoin unless it can be absolutely certain it gets a solid new member that will not cause this kind of upheaval again in the foreseeable future. 1/