Labour’s mayoral hopeful has slammed current incumbent Boris Johnson and the Government over the decision to reject hosting the Tour de France Grand Depart in the capital in 2017.

Sadiq Khan, who will be running for the top job at City Hall in 2016, has demanded Mr Johnson and ministers give a full explanation.

He said: “The Government has wasted a huge opportunity to sell London to the world and bring one of the world’s greatest sporting events back to the capital.

“Londoners deserve to know exactly what happened for the Tour to be cancelled at the last minute with little explanation. The Government and Boris Johnson have serious questions to answer.”

Race fans gathered at the Queen Elizabeth Olympic Park as the Tour de France came to east London on July 7, 2014

The Tour de France’s organiser Amaury Sport Organisation had said it was keen to return to the UK “as soon as practicable” with Manchester, Edinburgh and London in the frame to host the start of the race.

The capital enjoyed the Tour's cycling action in 2014 with a stage that started in Cambridge passing through the East End by Canary Wharf to finish in The Mall.

Also, the first two stages of last year’s race were held in Yorkshire.

A decade ago, London hosted the opening stage, but despite hopes the action might still be held in other parts of the UK the organiser has now turned its attention to Germany for the 2017 Tour.

Race fans gathered at the Queen Elizabeth Olympic Park for the 2014 Tour de France

Transport for London’s managing director of surface transport Leon Daniels has said cash was the main factor in the decision to rule out the capital.

Estimated costs for 2017 were expected to be far more than the £7million shelled out in 2007.

He told BBC Sport: “To ensure value for money we must make difficult choices. We have always said that the return of the Tour was subject to funding."