Bookmakers are set to take a battering if Rio de Janeiro is unveiled as the host city of the 2016 Olympic Games this Friday.

Along with Britain's other layers, Ladbrokes chalked up Chicago as the strong favourite to be chosen.

The Windy City, supported by US President Barack Obama, remains the narrow odds-on favourite at 10/11, but almost all of the money in the last 24 hours has been for their South American rival Rio.

Ladbrokes spokesman Robin Hutchison said: "Rio is the only city punters want to back and we've had to cut the odds on the Games going to Brazil to 6/4.

"If it carries on like this we'll be changing next summer's holiday plans from the Copacabana to Skegness."

Of the other cities still involved in the bidding, Tokyo are 6/1 and Madrid considered the 16/1 rank outsiders.

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