TFL boss to go in January but will continue to advise Ken Livingstone.

London鈥檚 first transport commissioner is to step down at the start of next year, the captial鈥檚 mayor announced on Friday.

Bob Kiley, architect of the congestion charge and an outspoken critic of using a public private partnership deal to overhaul the Tube, will leave on 31 January.

In his five years in the job he oversaw the biggest investment in London鈥檚 transport since World War II.

He will work as a consultant to mayor Ken Livingstone until the mayor鈥檚 term of office ends in 2008. Transport for London would not comment on the terms of the consultancy deal.

Transport for London said the Kiley was leaving because the city needed a commissioner who could take it through to the 2012 Olympic Games.

However there were rumours that disagreements between Kiley and TfL鈥檚 finance director, Jay Walder, had led to his departure. Transport for London would not comment on the rumours.

Kiley said: 鈥淚t has been a privilege to serve as London鈥檚 first ever commissioner for transport. TfL has more than proved it can deliver since it was formed five years ago.鈥

Ken Livingstone said: 鈥淚t has been a great personal pleasure to work with Bob who I consider to be one of the outstanding public servants I have encountered.鈥

Kiley was previously chief executive and chairman of New York鈥檚 Metropolitan Transportation Authority.

At the time of Kiley鈥檚 appointment, Livingstone said his pay package 鈥 拢2m over four years linked to performance 鈥 was 鈥渃heap at the price鈥 if he eased the capital鈥檚 transport crisis.