Mediobanca SpA, the Italian investment bank, has cut its stake in French cement supplier Ciments Francais to below 10 per cent, according to a notice Friday from Paris stock market watchdog the Autorite des Marches Financiers. Mediobanca now holds 9.1 per cent of the French company and 5.5 per cent of its voting rights. The move is the result of an equity swap which expires at the end of January, the notice said, without giving further details.