Toulon - Wales scrumhalf Rhys Webb will no longer feature for French Top 14 side Toulon after club owner Bernard Lemaitre hit out at the "dishonest" attitude surrounding the player's return home.
Webb, 31, was originally set to leave the three-time European champions at the end of the season to move back to the Ospreys.
Earlier this week, the Welsh Rugby Union announced Webb would be eligible to feature in this year's Six Nations after being given an exemption from a rule requiring players to have more than 60 caps if they wish to represent their country while playing abroad.
"His family is back in Wales, it's difficult for him. We made beach-sized amounts of time for him to be able to go back and see his family in Wales," Lemaitre, who took over majority ownership of Toulon from Mourad Boudjellal last month, told Sud Radio.
"All of a sudden we learn he has already signed for the Ospreys and his agent had already negotiated with the Welsh union that he can be selected. It's a dishonest attitude.
"It takes us to a situation where I think Rhys Webb will not play in the Toulon shirt again. The adventure will be cut short," he added.
Webb was left out of Toulon's squad as they hammered Castres 43-3 to move to third in the Top 14 table at Stade Felix Mayol.
The two-time British and Irish Lions Test player watched from the stands as his side - with France international Baptiste Serin playing scrumhalf - crossed for six tries against the ill-disciplined visitors who were shown three yellow cards.
Sanchez stuns Toulouse
Later on Sunday, title holders Toulouse lost for the first time in nine games as struggling Stade Francais won 30-18 at Stade Jean Bouin in French rugby's 'Clasico'.
The Parisians move up from bottom spot thanks to back-rower Sekou Macalou's two tries, a swashbuckling Gael Fickou and Argentina flyhalf Nicolas Sanchez's perfect display kicking at the posts.
Macalou and Fickou furthered their claims for a spot in France's Six Nations squad to be named on Wednesday with inspirational performances to claim their side's fourth victory of the campaign.
"We've started the New Year with a win, it feels good. Especially in a period when we were finding things difficult," 51-time international Fickou said.
"We showed a new side to us but the season is still long. We have to continue on this path," he added.
Springbok World Cup winner Cheslin Kolbe returned from a minor back injury for the champions to touch down for the first time this season.
The visitors travel to Connacht in the European Champions Cup next weekend looking to tie up a quarter-final spot as Stade host Zebre in a dead-rubber match in the Challenge Cup.