The message reads, in part:

"Today, an immense and strong man has passed on. This is a huge loss for the oil and gas industry and for all those who knew him. Mr Vyakhirev was committed to his work, a top specialist and founder of the world's largest oil company, Gazprom, which he led with confidence and professionalism through the turbulent times of the 1990s. Largely due to him and his team, today the company remains the key player on the global market and the basis of Russia's economy.

"Mr Vyakhirev was respected by his colleagues as a talented and firm leader, as well as an open person who was always ready to provide support.

Warm memories of Mr Vyakhirev will remain forever in our hearts."