Russian ambassador to EU says sanctions are a 'dead end'

Vladimir Chizhov, the Russian Ambassador to the EU, believes "no amount" of sanctions can produce "irrevocable damage to the Russian economy".

However he did express concern for the future of business links and joint ventures between Russia and companies in the European Union.

The EU has imposed sanctions following allegations that the Russians are arming separatist rebels in Ukraine.

UK Prime Minister David Cameron said sanctions would continue to tighten until Russia "decides to behave like any civilised country".