Deferred income tax - Movement on the deferred income tax account (Details) - GBP (£) £ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Deferred income tax
At 1 January	£ (66)	£ (57)
Exchange differences	27	2
Acquisition of companies and businesses	(446)	(8)
Credited to the income statement	14	(8)	£ 23
Credited to other comprehensive income	5
Charged to equity	(2)	5
At 31 December	(468)	(66)	(57)
Deferred taxation has been presented on the balance sheet as follows:
Deferred tax assets	43	42
Deferred tax liabilities	(511)	(108)
Deferred tax asset (liability)	£ (468)	£ (66)	£ (57)

The amounts of income taxes recoverable in future periods in respect of: (a) deductible temporary differences; (b) the carryforward of unused tax losses; and (c) the carryforward of unused tax credits. [Refer: Temporary differences [member]; Unused tax credits [member]; Unused tax losses [member]]

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The amount of tax expense or income relating to changes in deferred tax liabilities and deferred tax assets, recognised in profit or loss. [Refer: Deferred tax assets; Deferred tax expense (income); Deferred tax liabilities]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The amounts of income taxes payable in future periods in respect of taxable temporary differences. [Refer: Temporary differences [member]]

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The amount of deferred tax liabilities or assets. [Refer: Deferred tax liabilities; Deferred tax assets]

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The amount of deferred tax related to items credited (charged) directly to equity. [Refer: Deferred tax expense (income)]

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The increase (decrease) in deferred tax liability (asset) resulting from business combinations. [Refer: Deferred tax liability (asset)]

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The increase (decrease) in deferred tax liability (asset) resulting from the net exchange differences arising when the financial statements are translated from the functional currency into a different presentation currency, including the translation of a foreign operation into the presentation currency of the reporting entity. [Refer: Deferred tax liability (asset)]

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Deferred income tax relating to components of other comprehensive income

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