Narrowing a chimney breast

[Adam535]

I hope Somone can shed some light:

Can you narrow a brick chimney breast on a semi detached, the chimney in question is in the bedroom. Or would it become structurally unsafe?

I understand best way to do it is via Gallow bracket, but just wondering if 7cm from each side be possible without gallow bracket.

Look forward to your experiences

See photo attached

 

[bobasd]

please post a photo of the chimney breast .what youve posted looks like a drawing or somethin.
what whats the end result for this new openin?