I dunno. But I'm always a bit suspicious when such claims are made against 'official' enemies of the west - or traditional allies of 'official' enemies.
Re: Serbia election: Vucic claims big election victory for ruling party
A few months ago it looked like the Empire was going to open up a second front (Ukraine being the first (front)), but that seems to have fizzled out. I can't seem to find the reference : /.
Meanwhile, I cannot see Serbia joining the EU since it is nigh impossible to see Serb population accepting Kosovo not being a part of Serbia. My take.