You will need to review the guidance on residence, domicile and remittance to check what you need to declare on a Self Assessment tax return.
Residence, domicile and the remittance basis: RDR1
The UK deducts tax on the arising 'basis' on world-wide income. If you are a resident, but not UK domiciled, you have the option to use the remittance basis. This means any income or gains arising anywhere in the world, while you are resident in the UK, are only taxable in the UK, when you bring them into the UK.
Money spent on your foreign bank cards is condidered money remitted to the UK and needs to be declared.