Eurostar said: “Flooding in the Thames tunnels has been brought under control by Network Rail High Speed meaning at least one tunnel can now be used and a full service can operate.

“There will be some speed restrictions in place in the morning which may lead to delays and stations are expected to be very busy.

“Unfortunately, this unprecedented event has caused major disruption to customers today.

“Customers are encouraged to visit the Eurostar website for more information on their journey and compensation entitlement.”

Although Eurostar said services would return on Sunday, it warned of delays and busy stations.

The company said: “There will be some speed restrictions in place in the morning which may lead to delays and stations are expected to be very busy.”

The Met Office has warned there could be disruption to domestic journeys this weekend, as windy conditions sweep across the UK.

A warning for rain and snow has been issued for much of Scotland.

The cause of the leak is not yet clear.

Reports initially suggested the flooding was caused by a “fire control system”. In a statement, Thames Water said: “We have been informed of an incident involving a pipe flooding the Eurostar tunnel. We believe the incident is in regard to a fire control system and not a Thames Water pipe/asset, however we have a technician on the way to offer support to control the flow of water.”

But a spokesperson for HS1, which runs the route between London and the Channel Tunnel, said: “The source of the flooding will be the subject of an investigation, but at this stage we have no evidence to suggest that the fire control system was related to the issue in any way.”

After Eurostar cancelled trains today due to flooding, many turned to the other obvious mode of transport; air travel.

This led to air fares rocketing. Only one British Airways flight from Paris to London is available on Sunday, at a one-way fare of almost £700.

Latest here on the situation fronm Simon Calder

After a day of no services between Ebbsfleet and London St Pancras International due to flooding in the Thames Tunnel, Southeastern Railway says it will run a reduced service between Ashford, Kent, and St Pancras International in London tomorrow.

It added that it was still working on a plan for its high speed services tomorrow.

Why doesn’t Eurostar use one of its stations in Kent, on the “right” side of the blockage? Simon Calder explains:

The exact location of the flooding which caused such mayhem: the tunnel where the line dives beneath the Thames between Essex and Kent. On one side: London St Pancras International. On the other: Ebbsfleet International, which until 2020 was a regular stop on the line to the Channel Tunnel and France.

Although nothing like the full service could be run (there being only two Eurostar platforms), anything to reduce the upset among passengers desperate to get home would be worth trying. Another option: Eurostar couid serve the better-connected Ashford International, which has good conventional rail links with London, Kent, Surrey and Sussex.

Neither of them is a realistic option, I’m afraid. Were the two Kent stations in full working order, a plan could be cobbled together. But these are locations that have been mothballed and remain international stations only in name. To reboot the security set-up, get the immigration formalities resurrected and meet all the other operational requirements would be the work of weeks, not hours.

In the inevitable inquest after this dire end-of-year collapse, which has torn up the travel plans of more than 30,000 travellers, the idea of a back-up station may be raised. Eurostar, which says the Kent stations cannot possible reopen due to post-Covid finances and post-Brexit complications, will doubtless robustly explain why it would be a waste of resources to have a station on standby.

Since the tunnel incident was the first such calamity in 15 years of operation, I tend to agree – but I hope Eurostar will do more to have access to chartered coaches that could get at least some of the unfortunate passengers slowly to their destinations through the lovely Kent countryside.

Eurostar has just announced that services will return on Sunday after a day of cancellations on Saturday due to flooding in the tunnels under the River Thames.

The operator says the flooding is back under control, although speed restrictions may lead to delays.

All Eurostar services from London St Pancras have been cancelled today - ruining thousands of passengers New Years Eve plans.

Flooding occurred in railway tunnels near Ebbsfleet International station in southeastern England, affecting the High Speed 1 tunnel and another used by Southeastern.

A video taken inside the flooded tunnel shows water gushing onto the tracks from a pipe attached to the tunnel’s wall.

On Saturday afternoon, Thames Water revealed that the cause of the flood was an incident relating to a fire control system

We have been informed of an incident involving a pipe flooding the Eurostar tunnel. We believe the incident is in regard to a fire control system and not a Thames Water pipe/asset, however we have a technician on the way to offer support to control the flow of water,” they said in a statement.

“We will continue to monitor the situation and offer support where needed.”

Read the full report from The Independent’s Travel Correspondent Simon Calder here: