The UK has frozen the assets of six Russian prison bosses in charge of the Arctic penal colony where opposition leader Alexei Navalny died. 

The sanctioned individuals will also be banned from travelling to the UK.

Western leaders say the blame for Navalny’s death lies with the Russian authorities, including President Putin.

UK Foreign Secretary Lord Cameron said “those responsible for Navalny’s brutal treatment should be under no illusion – and the UK will hold them accountable.”

The UK is the first country to impose sanctions in response to his death, the Foreign Office says.