Ryanair-style railway carriages may loom for passengers on the East Coast main line with another Con-Dem hint at the return of third-class travel.

MPs are due today to debate the coalition's plans to put the publicly owned London-to-Scotland service back up for sale just four years after it rescued the route from debt-ridden privateer National Express.

An eyes-only circular for the route's bidders leaked last month proposed a new "intermediate class between standard and first" as part of the new franchise.