UK is increasingly following in the footsteps of the US regards proving eligibility to vote with photo ID expected to be mandated under the legislation.
https://www.theguardian.com/politics/2021/mar/09/warning-over-photo-id-law-change-for-uk-wide-and-english-elections
11 million electors (24% of the electorate) hold neither a passport nor a driving licence.
Photo identification has been required in Northern Ireland since 2003