SOCHI, September 23 (RIA Novosti) - Former French president Jacques Chirac and former German chancellor Gerhard Schroeder have arrived in the Russian Black Sea resort of Sochi on private visits, the Kremlin said on Sunday.

The ex-leaders traveled to Russia on the invitation of President Vladimir Putin, the Kremlin press office said.

On September 25, Schroeder will chair a shareholders' meeting in Sochi of Nord Stream AG, a company building a natural gas pipeline under the Baltic, of which the ex-chancellor is the supervisory chief.

State-controlled Russian energy giant Gazprom [RTS: GAZP] holds a 51% stake in Nord Stream AG, while Germany's BASF and E.ON own 24.5% each. Investment in the ambitious Nord Stream pipeline, designed to pump gas from Russia's Arctic to Europe, is estimated at 5 billion euros ($7 billion). The first leg is scheduled to be built in 2008-2010, and the second in 2010-2012.

The Black Sea resort city is currently hosting the final day of the Sixth International Investment Forum, which started on September 20. Russia's acting economics minister, German Gref, announced on Saturday that business contracts worth $22 billion had been signed at the event.

The forum has been focused on future investment in the development of Sochi's infrastructure up to 2020, and the construction of sports facilities in the city in preparation for the 2014 Winter Olympic Games.