Transport minister Kim Howells yesterday told MPs that the government may have to look for "other ways" of funding Network Rail.

The not-for-profit Railtrack replacement is set to increase its charges to train operators, which will eventually fall upon the Department for Transport.

But Howells said: "I'm not going to sit here and say 'I can guarantee we're going to get £8 billion or £5 billion or anything else [from the Treasury]'."