"It is good news that the operating profit made by Network Rail will be ploughed back into the industry rather than disappear into shareholders' pockets - it's a pity that can't also be said of train operations," RMT general secretary Bob Crow said.

"A huge contribution to NR's efficiencies has been the decision to bring maintenance back in-house, and it would make sense to complete that job and bring renewals work back in house too.

"There will now be speculation about bonuses, and we would hope after the controversy of the last few years that it is the people who get out there and deliver the work who will reap the rewards.

"Network Rail is far from perfect, but today's figures underline what could be achieved if the disastrous PPP on London Underground was scrapped - and it underlines the need to keep the East London Line's operations out of the privateers' hands," Bob Crow said.