Denton Hall has taken on American in-house lawyer Pat Seferovich as head of its Moscow office.
Seferovich, who will replace Larry George, comes from US oil company Occidental. He has spent the past five years in Moscow as vice-president of the company's Russian subsidiary involved in oil and gas projects in the CIS.
Malcolm Groom, head of Denton Hall's energy group, said: "We were lucky to find someone who had been there for five years and wanted to stay in Russia. He has extensive contacts in the Russian oil industry and with the regulatory authorities."
He added that the firm had been interviewing Seferovich to join the Moscow office when George left the firm to join US firm Steptoe & Johnson in the Russian capital.
Seferovich has not been taken on as partner, although Groom said: "As and when he returns to London, he will be considered for partnership."
The appointment is the latest in a rash of hirings in Moscow.