Transport Secretary Patrick McLoughlin MP has visited the Harbury landslip between Banbury and Leamington Spa to see the work Network Rail is doing to reopen the line.
About 350,000 tonnes of earth and rock slipped down the embankment close to the entrance of the Harbury Tunnel on January 31, leaving the railway line closed and routes between the two stations replaced with bus services.
Mr McLoughlin said: “I regret rail passengers are still being inconvenienced by this serious landslip, but Network Rail’s main priority is to re-open the line as quickly as possible and when it is safe to do so.
“I have seen how hard Network Rail engineers are working to resolve this situation, and train operators have told me they are doing everything possible to give passengers up-to-date information and to keep them moving.”
The key route links Birmingham to London Marylebone aand Birmingham with the south coast.
More than 50 freight trains and 19,000 on 150 passenger trains use the line every day.
Mark Carne, Network Rail’s chief executive, said: “Our priority is to re-open the line between Leamington Spa and Banbury as quickly as possible. Progress has been made and we have removed more than 30,000 tonnes of earth from the site.
“Passengers can be assured that we are using all available resources, and working around the clock, to reopen this railway line safely. I thank passengers for their patience and apologise for the inconvenience caused.”