Current tax liabilities (Details) - GBP (£) £ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Current tax liabilities
Uncertain tax provisions	£ 54	£ 57	£ 65
Interest arising on tax provisions which is included within other payables	6	12	12
Income tax paid	£ 77	£ 69	£ 64

The cash flows from income taxes paid or refunded, classified as operating activities. [Refer: Income taxes paid (refund)]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2022-03-24
-Paragraph 35
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2022-en-r&anchor=para_35&doctype=Standard
-URIDate 2022-03-24

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 7
-IssueDate 2022-03-24
-Paragraph 14
-Subparagraph f
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2022-en-r&anchor=para_14_f&doctype=Standard
-URIDate 2022-03-24

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration