I'm not sure about a contract termination at this point but Erik Ten Hag mentioned Ronaldo will not be included in the match squad to face Chelsea in the weekend but for what it is worth I think Ten Hag is being too hard on Ronaldo and not giving him opportunity to play and that is what gets Ronaldo furious. He loves to play and should be given the opportunity to show the world hes not finished yet.
If it is true that Ten Haag did not include Ronaldo in several of Manchester United's matches, then I believe Manchester United will find it more difficult to win every matches. After all, you still need Ronaldo, even when he doesn't score once. If Ten Haag pretends to be arrogant by rejecting Ronaldo, I believe this can be a boomerang for him self, because MU staff and board need Ronaldo for business purpose 
.So, he is suffering and now things are going into worst for both parties with this all most chances they could be done in winter transfer window with his best place is now Chelsea where he can do good because coach and owner both are looking for him into this club and having good results after his arrival even he can't play Champions League in this season and for this he has to wait for some more months.