CARDIFF Blues chairman Peter Thomas has issued a stark warning that Welsh rugby's exodus of star players will continue without increased funding.
Although Roberts' destination has yet to be announced, Paris-based Racing Metro are favourites for his prized signature.
Roberts, a British and Irish Lions Test player in South Africa three years ago, looks set to follow Wales colleagues Mike Phillips, James Hook, Gethin Jenkins and Luke Charteris by agreeing a lucrative contract in France.
The Blues have claimed that Roberts, who celebrates his 26th birthday today, rejected a deal with them that would have made him among the United Kingdom's highest-paid players.
Speaking on Tuesday about his playing future, Roberts said: “It's a very tough choice I have got to make, and one I haven't made yet.
“It's a huge decision and there are a load of factors to take into consideration. It's a tough one.”
Wales interim head coach Rob Howley has already delivered a blunt message about players' international prospects if they opt to move outside the Principality.
And that directly impacted on Howley's scrum-half selection for Saturday's clash against Argentina, with Scarlets number nine Tavis Knoyle, who trained fully in Spala, being preferred to the vastly more experienced Phillips.
Thomas said: “We have invested a lot of time, money and effort developing Jamie as a rugby player from an early age after identifying him as a star of the future.
“We have stuck by him through thick and thin and supported him during last season when he only completed two matches for the Blues because of his knee injury and international duties, playing 15 matches for Wales.
“It is impossible for the Welsh regions to compete with the kind of money that is on offer from other clubs in other countries.
“The time has come that the Welsh benefactors should not be responsible for funding the professional game.
“The chairman of the regions can guide companies, but if we want to keep Jamie Roberts and other international players in Wales then the governing body has to intervene.
“The player drain out of Wales, which has a negative impact on the Welsh regions and the national team, will only continue without increased funding from the governing body.
“As an example, with our recent game against Leinster the IRFU pay for 14 of their players and additionally fund the province for the remaining players in excess of €4m.
One way forward might be for the WRU to secure top players on central contracts, but WRU group chief executive Roger Lewis recently claimed that Wales' four professional regions - the Blues, Ospreys, Scarlets and Newport Gwent Dragons - rejected that idea.
Roberts, who is currently in the final academic year of studies to become a doctor, made his Wales debut in 2008 and has become a pivotal player during the Warren Gatland coaching era.
He returned to playing in September after being sidelined for six months with a knee injury. During that spell out of the game he missed Wales' three-Test Australia tour.
Holland added: “Given news of Jamie's departure, we will begin the search to find a suitable marquee player who will be eligible to play for us throughout the entire season.”