Foreign Secretary Dominic Raab said:
It is appalling that Alexey Navalny has been detained on arbitrary charges. The UK Government calls for his immediate and unconditional release.
Mr Navalny is the victim of a nerve agent attack, and the Russian authorities should investigate and explain the use of a chemical weapon on Russian soil.
Media enquiries
Email newsdesk@fcdo.gov.uk
Telephone 020 7008 3100
Email the FCDO Newsdesk (monitored 24 hours a day) in the first instance, and we will respond as soon as possible.