v3.25.2
Borrowings and lease liabilities - Schedule of borrowings (Details) - USD ($)
$ in Millions
 6 Months Ended 12 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2024
Disclosure of detailed information about borrowings [line items]      
Opening balance $ 1,984 $ 2,239 $ 2,239
Proceeds from borrowings 285 320 655
Repayment of borrowings 180 420 909
Finance costs paid on borrowings (48)   (114)
Interest charged to the income statement 53   114
Deferred loan fees 5   0
Translation 4   (1)
Closing balance 2,103   1,984
Non-current 2,017   1,901
Current 86   83
Reconciliation of finance costs paid (excluding lease finance costs)      
Finance costs paid on borrowings 48   114
Commitment fees, utilisation fees and other borrowing costs 6   12
Total finance costs paid 54 $ 63 $ 126
Geita multi-currency RCF      
Disclosure of detailed information about borrowings [line items]      
Proceeds from borrowings $ 285    
Reconciliation of finance costs paid (excluding lease finance costs)      
Borrowings maturity term 3 years    
Geita multi-currency RCF | United States of America, Dollars      
Disclosure of detailed information about borrowings [line items]      
Proceeds from borrowings $ 180    
Geita multi-currency RCF | Tanzania, Shillings      
Disclosure of detailed information about borrowings [line items]      
Proceeds from borrowings 105    
2022 multi-currency RCF      
Disclosure of detailed information about borrowings [line items]      
Repayment of borrowings 180    
Reconciliation of finance costs paid (excluding lease finance costs)      
Notional amount $ 1,400