One of France's most powerful shareholder groups has moved to quell takeover speculation around French utility company Suez by calling for the Autorité des Marchés Financiers to investigate claims of insider trading in the company.

French political magazine Marianne reports that Belgian financier Albert Frère is examining a bid for Suez alongside French luxury goods billionaire, Bernard Arnault, owner of LVMH, after Frère raised his stake in Suez from 8% to over 9%.