Crack above window frame

[Fjordvik]

Hello all,

Wonder if anyone can help. I've attached a photo of a crack that runs across the top of my window frame. Note the outside had a brick arch which has been missing a cover at the top section (please see the two photos of the window missing the cover and another window with one).

Should I be concerned of this crack? The other windows cover doesn't seem to be load bearing just to stop water ingress. Note I can slide a knife into this crack quite high without hitting resistance.

Thanks in advance

 

[blup]

Looks like the shrinkage you would expect with plaster.

Blup

 

[Notch7]

its a shame the window is fitted so close to the outside -no wonder the weather has got to it

 

[JohnD]

Do you mean the gap where the plaster ceiling almost meets the wall?