(Reuters) – Vagit Alekperov was a former Soviet assistant oil minister who supported close ties between Russia & OPEC. He resigned as the president of Russia’s second largest oil producer Lukoil, and its board of directors, according to the company.

Lukoil has not stated why Alekperov aged 71 resigned nor who would be taking over. Britain placed Alekperov under a travel ban and asset freeze last week in response to Russia’s military operations in Ukraine.

Sources close to the matter claim that Alekperov (ranked 10th in Russia by Forbes) decided to leave his post after being sanctioned. This was to safeguard company operations. According to another source, the board was set to elect a new chief.

After being sanctioned several Russian businessmen have been forced to resign from high-ranking positions, or give up their control of companies.

Alekperov of Azeri descent has always been an avid supporter of Russia’s cooperation with the Organization of the Petroleum Exporting Countries. Moscow played a significant role in the informal group, OPEC+ in deciding production policies.

Lukoil, like other Russian companies, stated last month that it was worried about “tragic events” in Ukraine and called for an end of the conflict.

Lukoil is named after the West Siberian oil town of Langepas Urai and Kogalym. Its oil production grew to around 1.6million barrels per day last year. This figure is about half of what countries such as Kazakhstan or Qatar produce.

Its biggest asset is West Qurna-2, an Iraqi oilfield that produces over 400,000 barrels per day.

Alekperov was appointed in 1990 as deputy minister for the oil and gas sector of the Soviet Union. He became the company’s president and chief executive officer.

He said that in 2018, he thought about the person who would succeed him. He stated, “It will be none of my close relatives,”

Lukoil claimed that Alekperov had 3.12% share of the company shares as of March 31st and was the beneficiary of another 5.43 percent of shares through family trusts.