Segmental information - Geographical analysis (Details) - GBP (£) £ in Millions	6 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Disclosure of geographical areas [line items]
Sales	£ 13,219	£ 11,753
United States
Disclosure of geographical areas [line items]
Sales	3,617	3,072
India
Disclosure of geographical areas [line items]
Sales	1,599	1,704
Great Britain
Disclosure of geographical areas [line items]
Sales	1,163	1,204
Rest of World
Disclosure of geographical areas [line items]
Sales	£ 6,840	£ 5,773

The income arising in the course of an entity's ordinary activities. Income is increases in assets, or decreases in liabilities, that result in increases in equity, other than those relating to contributions from holders of equity claims.

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+ Details