UPDATE 1-Britain names Russian envoy, hopes for better ties

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By David Clarke

LONDON, March 28 (Reuters) - Britain named an experienced eastern Europe expert as its new envoy to Russia on Friday and said it was seeking opportunities to improve ties with Moscow, which are at their chilliest since the Cold War.

Britain's Foreign Office said Anne Pringle would replace Anthony Brenton in October when he leaves the high-profile post he has occupied for four years, but rejected speculation the change was due to worsening ties between the two countries.

"We are looking for opportunities to improve our relationship with Russia," said a Foreign Office spokesman. "With a new president taking office, we hope to see greater Anglo-Russian cooperation on a number of issues."

Britain and Russia have tens of billions of dollars in trade and bilateral investments -- including major stakes in oil projects held by BP (BP.L) and Royal Dutch Shell (RDSa.L).

Pringle, one of a small band of senior women at the Foreign Office, has been director for strategy and information for the past three years, before which she was ambassador to the Czech Republic. She worked in Moscow from 1980 to 1983.

LOW EBB

Ties between London and Moscow are at a low ebb, partly because of Russia's refusal to extradite a former KGB agent wanted for trial in Britain for the murder in London of a Russian critic of the Kremlin who had taken British citizenship.

That led to diplomats being expelled from both countries and to the forced closure of two regional offices in Russia of the British Council, the cultural arm of the British government.

In 2007, activists from the pro-Kremlin youth organisation Nashi launched a campaign against Brenton, picketing the embassy and venues where he was expected to turn out, interrupting his speeches and banging their fists on his diplomatic car.

Britain hopes the change of guard at the Kremlin could be a catalyst for warmer relations. President-elect Dimitry Medvedev takes over in May from Vladimir Putin, who will stay on in the role of prime minister.

"We hope Medvedev will embark on a fresh start in his relations with us. We want to improve our relationship," the Foreign Office spokesman said. (Additional reporting by Adrian Croft; editing by Peter Millership)