Wales defence coach Shaun Edwards is being allowed to work with Toulon this season.
But Edwards will not be allowed to spend time with the French giants before their Champions Cup pool games against the Scarlets.
The WRU have confirmed that the ex-rugby league legend – who is contracted to Wales until the 2019 Rugby World Cup – will only work with the Top 14 outfit outside of international commitments.
“Shaun will be with Toulon on a CPD (career professional development) basis,” said a WRU spokesman.
“We also want to stress that he will not work with Toulon for two weeks before their Champions Cup matches against the Scarlets.”
Edwards, a key member of Warren Gatland’s back-room team since 2008, is widely regarded one of the best defence coaches in the game.
He signed a fresh four-year extension to his WRU contract last December.
The Edwards-Toulon speculation was first revealed two months ago.
At the time, a WRU statement read: “Shaun is contracted to Wales through to 2019.
“The WRU and national squad have a close working relationship with Toulon.
“As normal practice in this environment there is always coaching CPD (continued professional development) and exchange of ideas and experience.
“Toulon coaches have spent time with us and we do that reciprocally and that is the situation here.”