Former German Chancellor Gerhard Schroder was was nominated on Friday to serve on the board of Russian state energy giant Gazprom.

Schroder, who led Germany from 1998 to 2005, is a Social Democrat and friend of Russian President Vladimir Putin. His links to Russia are often the source of controversy, including within his own party, which leads the new coalition government.

His appointment to Gazprom's supervisory board will be finalized at the annual general meeting on June 30.

Schroder will replace Timur Kulibayev, a son-in-law of former Kazakh president Nursultan Nazarbayev. Kulibayev was ousted from his position in the wake of violent unrest in Kazakhstan in January.

Schroder already has a number of high-ranking positions in Russian business.

The 77-year-old is chairperson of the supervisory board of state energy company Rosneft.

He is also chairperson of the shareholders' committee of Nord Stream AG and president of the board of directors at Nord Stream 2 AG.

Both gas pipelines connect Russia and Germany via the Baltic Sea. Critics of Russia, most notably the United States, have said that Nord Stream 2, which is not yet in operation, could be used as leverage against Moscow if it stages a military incursion in Ukraine.

Ukraine's demands for arms deliveries from its Western supporters amid spiraling tensions at its border with Russia have been described by Schroder as "saber-rattling."

He has also blamed NATO for Russia's mass deployment of troops at the border.