Please remember that there is no automatic right of entry to licensed premises nor is there an automatic right to service of alcohol. Entry is always at the discretion of the licensee for whatever reason he or she decides and the licensee is under no obligation to explain the reason.
Recommended forms of I.D
(i) A passport 
(ii) A European Union photocard driving licence
(iii) A Ministry of Defence Form 90 (Defence Identity Card)