If you are resident in the UK, but not domiciled, and you do not bring this income into the UK, then it is not taxable in the UK and you do not include it on a Self Assessment return.
If at some point in time, you bring it in to the UK, you will need to declare it on your Self Assessment return in the year you bring it to the UK. You can claim for tax relief on foreign tax paid on this income. You can see the guidance on residence, domicile and remittance to see how this affects you here:
Residence, domicile and the remittance basis: RDR1
If you are declaring this income on your tax return, you would use the figure after pension deduction, so that you can recieve tax relief on your pension payments. The maximum relief for pension payments is £40000 and this figure could reduce, depending on your total income.