v3.25.2
Net finance costs (Details) - GBP (£)
£ in Millions
 6 Months Ended 12 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2024
Disclosure of attribution of expenses by nature to their function [line items]      
Net finance costs £ 969 £ 305  
Gain related to tender offer   590  
Tender offer   1,800  
Tender offer accrued interest and other costs   3  
FV loss on derivatives £ 4 £ 23  
Proportion of average cost of debt 5.10% 4.90% 5.30%
Coupon on perpetual hybrid bonds net of tax £ 22 £ 21  
Financial liabilities at fair value      
Disclosure of attribution of expenses by nature to their function [line items]      
FV loss on derivatives   28  
Reported at CC      
Disclosure of attribution of expenses by nature to their function [line items]      
Net finance costs £ 885 821  
Percentage increase in net finance cost 7.80%    
FII GLO      
Disclosure of attribution of expenses by nature to their function [line items]      
Interest related to FII GLO £ 19 31  
Canada      
Disclosure of attribution of expenses by nature to their function [line items]      
Net finance costs 59    
Interest expense 10    
Brazil      
Disclosure of attribution of expenses by nature to their function [line items]      
(c) Romania other taxes 3 15  
Netherlands      
Disclosure of attribution of expenses by nature to their function [line items]      
Interest expense £ 3 £ 5  
British Pound      
Disclosure of attribution of expenses by nature to their function [line items]      
Increase in exchange rate 1.70%