Retirement benefit obligations - Schedule of Defined Benefit Pension Expense (Details) - GBP (£) £ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
|
| RETIREMENT BENEFIT OBLIGATIONS (Details) - Schedule of Retirement Benefit Charges to Income Statement [Line Items] | |||
| Charge for the year | £ 64 | £ 85 | £ 88 |
| Net interest amount | (165) | (166) | (208) |
| Past service cost – plan amendments | 30 | 35 | 5 |
| Plan administration costs incurred during the year | 32 | 33 | 35 |
| Total defined benefit pension credit | (37) | (11) | (79) |
| Defined benefit pension schemes | |||
| RETIREMENT BENEFIT OBLIGATIONS (Details) - Schedule of Retirement Benefit Charges to Income Statement [Line Items] | |||
| Total defined benefit pension credit | £ (39) | £ (13) | £ (80) |