Apple tree dieing back

Hey,

I have an apple tree and for the last two years it has started to come into leaf and then blossom and then it dies back about 20% to dead wood (which doesnt then leaf next year).

I thought it was being strangled by a large bush growning under it (as well as 2 rose bushes growing up it) so I move the bush but is still died back again this year.

I dont want to lose the tree but Im not sure what to do - any help please?

With Thanx

Are tghere any other symptoms such as sunken patches of bark, or oozing from the tree?

Hey,

Ive had a good look over the tree - and tried to take some pictures - there are some leave growing back and I noticed only 2 small patches on one branch which has some white feathery 'mould' but nothing else.

Im not sure what sunken patches of bark look like and there is nothing oozing.

Thanx you so much for getting back to me.