The developer behind the Rail Central plan bought up the land before looking for a project, a county MP has claimed.
The rail depot plan, led by Ashfield Land, is proposed for an eight million sq ft area between Milton Malsor and Blisworth.
Villagers have repeatedly questioned whether the site is the only area where the scheme could be built, and why no others seem to have been considered.
Andrea Leadsom, the local MP for Blisworth villagers, said: “Ashfield Land seems to have bought the land / obtained option agreements and are therefore looking for a project that they can develop.”
The issue has been raised by Mrs Leadsom in a meeting with rail minister Claire Perry, and she is awaiting a response.
In reply to Mrs Leadsom, Ashfield Land insisted the meeting of the M1, the A43 and a branch line made the site the best location for a rail depot.
Claire Cope, planning director for Rail Central, said: “We are strongly committed to delivering a new strategic rail freight interchange and the connectivity of the site at the meeting of three major transport routes – the West Coast Mainline, the Northampton Loopline and the M1 via the A43 - make this an ideal location.
“Rail Central is responding to a clear national need for more goods to be transported by rail, will help to create jobs and contribute to the local and regional economy.”
Mrs Leadsom also asserted that there is existing capacity at the nearby Daventry International Rail Freight Terminal, which is undergoing expansion, and the East Midlands Gateway Rail Freight Interchange, which was granted a development consent order last month.
A public consultation will begin in April.