Euston station could be demolished after an apparent U-turn by the government over plans for a new high speed railway.
Eleven new platforms are due to be built at Euston to form the southern terminus of the £42bn HS2 line to the Midlands and the North.
The current proposal involves shoe-horning the new tracks and platforms into the existing station.
The new chairman of HS2, Sir David Higgins, has been asked to draw-up a report for the government as a part of his review of the project.
An earlier plan to demolish Euston was scrapped last April amid growing concern about the impact on nearby residents.
HS2 has provoked anger in Camden where up to 500 homes are under threat.
A spokesman for the Department for Transport said: "The Chancellor is absolutely right to point out the fantastic opportunity HS2 provides to regenerate Euston."
The station was last rebuilt in the 1960s and is regarded as the Ugly Sister of London's mainline stations.