FINANCIAL LIABILITIES AT FAIR VALUE THROUGH PROFIT OR LOSS (Details) - Schedule of Trading and Other Financial Liabilities and Fair Value Through Profit or Loss - GBP (£) £ in Millions	Dec. 31, 2020	Dec. 31, 2019
Disclosure Of Trading And Other Financial Liabilities At Fair Value Through Profit Or Loss [Abstract]
Liabilities designated at fair value through profit or loss: debt securities in issue	£ 6,828	£ 7,531
Trading liabilities:
Liabilities in respect of securities sold under repurchase agreements	14,996	11,048
Other deposits	6	98
Short positions in securities	816	2,809
Financial liabilities at fair value through profit or loss that meet definition of held for trading	15,818	13,955
Total financial liabilities carried at fair value, excluding derivatives	£ 22,646	£ 21,486

The amount of financial liabilities that meet either of the following conditions: (a) they meet the definition of held for trading; or (b) upon initial recognition they are designated by the entity as at fair value through profit or loss. An entity may use this designation only when permitted by paragraph 4.3.5 of IFRS 9 (embedded derivatives) or when doing so results in more relevant information, because either: (a) it eliminates or significantly reduces a measurement or recognition inconsistency (sometimes referred to as ‘an accounting mismatch’) that would otherwise arise from measuring assets or liabilities or recognising the gains and losses on them on different bases; or (b) a group of financial liabilities or financial assets and financial liabilities is managed and its performance is evaluated on a fair value basis, in accordance with a documented risk management or investment strategy, and information about the group is provided internally on that basis to the entity’s key management personnel (as defined in IAS 24). [Refer: At fair value [member]; Key management personnel of entity or parent [member]; Derivatives [member]; Financial assets; Financial liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 8
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_8_e&doctype=Standard
-URIDate 2020-01-01

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