The proposed acquisition of logistics services company Geodis would create Europe's fourth largest transport and logistics company, says Guillaume Pepy, SNCF chairman.
After a review of the offer and various analyses and reports submitted to the Geodis board, board members voted unanimously to recommend shareholders accept the offer.
SNCF currently holds a 42% stake in Geodis, making a counter offer by another group unlikely.
Unions representing SNCF's workers were cautious in their response. The Financial Times reported that the Sud-Rail union had raised concerns that SNCF was attempting to change the status of the freight business by "submerging it in a company with the statutes of a private group."
For a cash outlay of about €600 million ($935 million), the deal would create a group with sales of €7.7bn ($12 billion).
Geodis reported 2007 revenues of €4.8 billion ($7.48 billion) and has a network spanning 120 countries.