The announcement was made on Monday morning
French Top 14 rugby teams Racing 92 and Stade Français will merge from next season.
The announcement, made on Monday morning, will see two of the biggest sides in French rugby join together and pool their resources.
In a statement today, Racing say the move "must give birth to a new club that will preserve the roots of Racing 92 as those of the Stade Français Paris while multiplying the means put at the service of youth and French rugby."
The two sides collectively have won 20 Top 14 titles, more than any other team in the league. Racing 92 last year lifted the crown and also made it to the final of the Champions Cup, only to be beaten by English Premiership side Saracens.
"Winners of the first two championships in the history of French rugby in 1892 and 1893, Racing 92 and Stade Français Paris also won the Brennus Shield in the last two seasons," Racing said in a statement today.
"These two flagship clubs of Paris and the Hauts de Seine, beyond the sporting rivalry they have enjoyed, have many other similarities: a strong local and regional anchoring, a historic educational mission, ancestral ties with The Olympic movement or an inextinguishable will to progress in all areas.
"It is on the basis of these principles that the two clubs lay the foundations for a merger project by pooling their resources to better cope with the challenges of performance and education.
"This association, effective from next season, must give birth to a new club that will preserve the roots of Racing 92 as those of the Stade Français Paris while multiplying the means put at the service of youth and French rugby.
"Consolidated by its dual culture, by the fierce determination of its two presidents and its increased audience in a population pool unmatched in France, this new club has a long-term commitment to build a true reference day after day."