Eurostar has cancelled all of Saturday's services to and from London St Pancras due to flooding in a tunnel under the River Thames, throwing new year travel into chaos, reports BBC News.
This morning, Eurostar said it hoped later services could run but by 14:00 GMT had cancelled all 41 trains.
All Southeastern's high-speed services to Ebbsfleet, which use the same line, have also been cancelled.
Many passengers have been scrambling to rearrange New Year's Eve plans.
A video taken inside the flooded tunnel shows water gushing onto the tracks from a pipe attached to the tunnel's wall.
Thames Water said a "fire control system" was likely to have caused the flooding rather than one of its own pipes.
Eurostar, which runs services from London to Paris, Brussels and Amsterdam, said affected customers were entitled to a full refund or exchange.
It is not known yet whether services will resume on Sunday but HS1 conceded on Saturday evening the problems would "take time" to resolve.
At a crowded St Pancras on Saturday morning, disappointed travellers sat on suitcases, frantically trying to find alternative routes.