[Dan Salter]

I am not in any way accusing you of a wind up...or of a big bird or whatever being placed in the picture by a joker....i am though TELLING you that you need to look at the pic with a photographers and birders knowledge and we are all saying that the bird is in flight and close to the camera...it happens a lot and can create funny looking illusions as it has here.

The general 'jizz' of the bird...is that its a passerine (small perching bird like a sparrow or tit size) it does not have the 'jizz' (overall shape, sillhouette, feeling, body proportions, eye size etc ) of a large bird..but it does have all the proportions of a small bird that now 'looks' large....i can see wing movement (flight).
As for ID...that is a little tricker due to the fuzzyness and bad quality of the pic...i agree on greenish belly, black band, white head and what look like dark eye patches but tits like blue or great tits can come in many colour defections or 'mutations'....