Lance Armstrong was paid A$1.5 million by South Australia's government for comeback Tour Down Under

The South Australian government paid Lance Armstrong A$1.5 million (at the time equivalent to £670,000) to take part in the 2009 edition of the Tour Down Under, the first race of his comeback season.

The figure has been revealed for the first time after a clause banning the parties to the contract from revealing its details for 10 years expired, reports Daily Mail Australia.

Because the contract did not include any clause relating to doping or cheating, Armstrong – banned from cycle sport for life in 2012 after a United States Anti-Doping Agency investigation – did not have to return the money.

Under the contract, Armstrong also received two first-class return plane tickets as well as hotel rooms.

At the time, the state government was controlled by the Labor Party, its 17-year rule coming to an end last year when the Liberal Party won the state election.

“South Australians have a right to know this information,” said state treasurer Rob Lucas. “We tried to release it straight after the election but couldn't legally under the terms of the contract, which explicitly prevented either party from publicly disclosing its details for 10 years.”

He added that the contract did not require Armstrong to race the Tour Down Under itself, but rather the Tour Down Under’s Cancer Council Classic criterium in Adelaide that acts as a curtain-raiser to the main race.

Riding for Astana that season, Armstrong finished the Tour Down Under in 29th place overall. He would return to the race for the following two seasons with Radioshack, receiving further appearance money.

The 2011 edition turned out to be his final race, with Armstrong announcing his retirement from the sport for good.

By that time, he was facing a federal investigation into allegations of doping, and although that probe would be shelved, the testimony gathered would help lead to hi ban.

His appearance at the 2009 Tour Down Under is estimated to have helped South Australia achieve a return of A$39 million from the race, up from $22 million the previous year.