A Lloyd�s of London insurer is offering up to 1 million euros ($1.3 million) in exchange for clues that could recover jewels worth an estimated $136 million seized in a heist in the French Riviera resort of Cannes last month.

The broad-daylight looting by a lone thief of precious jewelry on exhibition at the Carlton Hotel was France�s biggest ever gem theft.

�A reward of up to 1,000,000 euros pro rata is offered to the first person who provides information which leads to recovery of the goods,� SW Associates, a Paris-based loss adjuster and risk manager working for Lloyd�s of London, said in a statement.

The statement, with photographs of two diamond rings, a brooch and a necklace from among the stolen pieces, will be published in Le Parisien, Nice-Matin and the International Herald Tribune newspapers on Wednesday, SW Associates Managing Director John Shaw told Reuters.

He said it was hoped the reward was enough to encourage a witness, a person close to the robbers or someone who has been approached to buy the jewels to come forward with information.

Any payout would take time. �We have to get the jewelry back first, evaluate the value of the recovered jewelry and then, once the police is satisfied we�re not about to recompense the robbers, we can arrange the payment,� Shaw said.

The heist took place around midday when a thief wearing a cap and scarf and armed with an automatic pistol burst into the Carlton, threatened security guards and sales staff and left moments later with a briefcase containing 72 pieces of jewelry from a collection belonging to diamond specialist Leviev.

In 2008, SW Associates offered a $1 million reward for information about a $105 million jewel heist from the Harry Winston store in Paris and recovered more than half the stolen pieces thanks to a person coming forward. ($1 = 0.7553 euros)

(Reuters)