London Underground staff have rejected a pay offer of a £500 bonus for working on shift during the Olympics.
The Rail, Maritime and Transport Union (RMT), which represents thousands of Tube staff, said the money was not an adequate reward for being on duty during the event, as it will attract so many more passengers.
According to london24.com, the union has highlighted other deals has guidelines, including one of £1,100 at Docklands Light Railway, and £600 at London Overground.
The RMT general secretary Bob Crow told the BBC: "It is well-documented that transport will be the biggest logistical challenge throughout the Olympics period.
"All we are calling for is a fair deal for all the staff involved in delivering the colossal transport challenge that we will be facing this summer and the negotiations to achieve that are ongoing."
London Underground director George McInulty told london24.com: "This summer LU staff will be asked to work flexibly, and we are determined to properly acknowledge the contribution they will be making to a fantastic Olympics and Paralympics Games while keeping London moving."
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