Nearly 200 workers employed by Tube Lines contractor ISS face being laid off, the Rail Maritime and Transport (RMT) union has warned.

The RMT has called on London Mayor Ken Livingstone, who said the company could not justify the job cuts, to step in and halt the planned losses.

Tube Lines said it was "refocusing resources" for station cleaning.

Mr Livingstone has said London Underground (LU) maintenance firm Tube Lines has "no reason" to axe hundreds of cleaners' jobs as the company was profitable.

It is time for the mayor, Transport for London and London Underground to tell Tube Lines that it cannot impose this massive cut Bob Crow, RMT general secretary

"I do not see how they can maintain standards of cleanliness by cutting staff," he said.

"Given the profits that the infrastructure companies enjoy, there is no case for reducing these cleaning posts."

On Thursday, RMT general secretary Bob Crow said workers were "stunned and furious" when they were told their jobs may be axed.

'Innovative solutions'

He also said the union was originally led to believe 100 jobs would be cut but the figure has turned out to be double that.

"RMT will use every means available to stop these job cuts, but it is time for the mayor, Transport for London and London Underground to tell Tube Lines that it cannot impose this massive cut," Mr Crow said.

He said it would be impossible for levels of station and train cleanliness to be maintained on the Jubilee, Northern and Piccadilly lines with a loss of 27% of the cleaning workforce.

A Tube Lines spokesman said the company was continuing to invest in "innovative solutions" to improve stations' appearance, such as anti-graffiti film.