France's SOCIETE GENERALE has increased its stake in private Russian bank ROSBANK from 10% to 20% for USD 634 mil, with a purchase option for a further 30% to enable it to take control of the bank by 2008, for a total investment of between USD 2.3 bn and USD 2.6 bn. INTERROS currently holds 90% of ROSBANK's shares, and it will become a shareholder in SOCIETE GENERALE. ROSBANK will soon have 1225 branches, and is growing fast, with net profits of USD 587 million last year.