Toulon will seek compensation from Quade Cooper if he does not honour his contract with the club.
In April this year, the European champions confirmed they had secured the Wallabies flyhalf's services, but the player's agent Khoder Nasser and his Vodacom Super Rugby franchise, the Queensland Reds, rubbished those reports at the time.
On Sunday, however, it was revealed that the 27-year-old had inked a new four-year deal with the Australian Rugby Union with the aim of playing at the 2016 Olympics.
Toulon now look set to take legal action against the playmaker, who will have to buy his way out of the French contract.
'Quade Cooper has signed a contract and the document was submitted in due form to the National League,' Toulon president Mourad Boudjellal told local newspaper La Provence.
'I do not know the exact amount of the contract price, but a compensation clause was included in the first agreement with an established tariff if the player did not sign the contract to follow. If he does not respect this contract, the compensation clause will come into effect and the amount will be very high,' Boudjellal fumed.
Cooper currently sits on 53 Test caps, meaning he falls short of the 60 required to be eligible for Australia while playing overseas, but he is expected to reach that threshold before the end of the World Cup.
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