Work to clear the embankments of railway lines near Bicester is underway ahead of a judicial review into the East West Rail link.
More than 50 per cent of the route between Bicester and Islip has now been cleared in readiness for the Oxford to Bicester section of East West Rail.
John Elvin, treasurer of the Oxon and Bucks Rail Action Committee, said the work to expose the track bed and embankments would allow engineers to see what work will need to be done when the line comes to be rebuilt.
He added: “It will be an absolute boost for the area and for people wanting to take jobs in Oxford.
“It also has a great cost-to-benefit ratio.” A judicial review into the scheme is due to heard in March, and construction work cannot begin until it has reached a conclusion.
The review is expected to take up to three weeks.
Network Rail, which is now working in partnership with Chiltern Railways to deliver the Oxford to Bicester section, said it could not comment on timescales for the work until the judicial review is over.
A Network Rail spokesman added: “Following the outcome of the review, we will certainly be communicating more to passengers and people in the area.
“It is our aim to complete the Oxford to Bicester upgrade as quickly, efficiently and safely as possible.”
The ambitious plans, which now incorporate Chiltern Railways’ Evergreen III project, will provide a half-hourly London Marylebone to Oxford service via Bicester.
A new section of track will be installed to link the Oxford to Bicester line with the Banbury to Marylebone line, just south of Bicester North station.
Bicester Town station is also due for a major facelift.
Dr Ian East, chairman of the Oxford to Bicester Rail Action Group (OBRAG), has lodged a complaint against Network Rail for its failure to publish its plan of works.
In a comment on the OBRAG website, Dr East added: “Quite how any engineering company can have no plan of works just weeks before starting a £200m project (as a former engineer myself) confounds me.
“I wish I could be more optimistic. Our best hope lies in oversight by Chiltern Railways, who (unlike Network Rail) have much to lose through delay.”
Dr East said he had asked the Office of Rail Regulation to press for more information on how the Oxford to Bicester service could be kept open for as long as possible.
He also said Chiltern Railways was obliged to offer buses in lieu of disrupted rail services, but said Chiltern would not discuss the plans until after the judicial review.