LONDON, Aug 16 (Reuters) - The London Metal Exchange on Tuesday banned Russian nickel from its approved warehouses in Britain unless it was exported before July 20.

The move follows a decision on April 1 to ban other Russian metals including copper, lead, primary aluminium and aluminium alloy from British warehouses. 

That was in response to the British government placing 35% additional duties on those metals as part of a package of sanctions on Russia following its invasion of Ukraine, which it has now extended to nickel.

The exchange said there was currently no Russian nickel stored in its British warehouses.

The LME, owned by Hong Kong Exchanges and Clearing Ltd (0388.HK), said in a statement that there was significant risk that someone receiving such metal from British warehouses would be hit with very high additional costs.

Britain has two approved locations for LME warehouses, in Hull and Liverpool. The latter currently has 198 tonnes of nickel stored there.