The French attorney-general yesterday asked the Paris appeal court to reject an application by Societe Generale and Paribas for BNP's hostile bid for the two rival banks to be ruled illegal.

Societe Generale and Paribas were seeking a ruling that the French stock market authorities should not have allowed BNP's bid for the two banks at a time when the two institutions were already planning a two-way merger.

The state prosecution supported the argument of the stock market authorities, the COB and CMF, which had originally ruled the bid legal.

Lawyers for the COB and CMF argued yesterday that BNP's share-swap offers for Societe Generale and Paribas were "unambiguous", "coherent" and "sufficiently explicit" to be allowed to go ahead.

BNP took the market by surprise in March when it launched its share swap offer for the two rival banks.