Members of a rail user group have slammed TfL for halting the Met Line Extension due to “inexplicable cost rises”.

The plans were rejected by the Mayor of London Sadiq Khan in January despite additional government funding of an extra £73 million being put forward.

Leslie Freitag, a committee member of the Watford Rail Users Group, disagrees with Mr Khan’s argument that the extension would not benefit people in north London as well as Hertfordshire – despite the line going through Harrow and Euston .

Mr Freitag added that suggesting a guided bus route as an alternative showed a “lack of understanding” about the area.

The rail group has since written to the Government’s Transport Committee warningas they say TfL’s demands for more money on top of the £358 million already raisedare “getting out of hand”.

Mr Freitag said: “Where is the money going? There is nothing to show for it and people are playing with large sums of money even though nothing is charging.

“We think the committee may well to be able to bore down into the obfuscation of rocketing price hikes. We would like it to happen but not to the extent that other schemes being affected such as the Abbey Line due to financial reasons.”

“The bus route shows a complete lack of understanding of the locality not to mention benefits of rail over road. Rail users especially from the north wouldn’t dream of changing to a bus to catch another train.

“We cannot go along with TfL’s demands.”

A spokesperson for the Mayor of London responded: “The previous Mayor committed £49 million of London taxpayers’ money to this scheme without bothering to work out how much it would actually cost.

"He also agreed for TfL to take all the risk of additional costs, even though the extension is for the benefit of people living outside of London. Since then a detailed review has shown that TfL would need to more than double its funding commitment to complete this scheme.

“The Mayor and TfL have proposed several pragmatic solutions to this, but without a pragmatic approach from the Government, the scheme cannot progress with such a huge financial risk to London taxpayers. The Mayor remains open to  finding alternative schemes that may be more affordable.”

The Watford Rail Users Group committee will be holding an Open Meeting tonight at 6.45pm.

It will be held in the first floor meeting room of The Junction in the offices located above Watford Junction Station.

For anyone unable to attend, queries can be directed to the secretary at email: wrug2@hotmail.co.uk