The European rail operator had hoped to resume normal operations on Monday (6 July), but a spokesperson for the brand has since told TTG it now does not expect a return to normal service before Tuesday (7 July).
Diversions via Utrecht are currently adding around an hour to journeys. Trains running between the Netherlands, Brussels and Paris are also being diverted via Utrecht with similar delays.
ProRail, which manages and maintains the rail network in the Netherlands, said the fire had affected a cable duct near Rotterdam Centraal on 29 June, affecting power supplies and bringing trains to a standstill.
In an update issued on Monday, ProRail said while repair work was "in full swing", no trains would run on the route until at least 5am on Tuesday, although it hopes to run a test train on Monday afternoon.
"With these test runs, we are checking, among other things, whether all systems are working properly," said ProRail, before warning: "It is possible that new points of attention will emerge during this process. At this moment, we cannot anticipate the results."
Eurostar said its services would continue to experience disruption across the Netherlands. Impacted travellers can change their bookings for free, or request a refund if they no longer wish to travel.
"We understand how disappointing and stressful this situation has been for everyone whose travel plans were disrupted," said Eurostar. "While the infrastructure damage was outside of Eurostar's control, we sincerely apologise for the impact it has had on our customers.
"Our teams remain fully mobilised to support affected travellers and are doing everything possible to help them reach their destinations or find the best available alternative case by case."
The Foreign Office updated its travel advice for the Netherlands on Monday morning, warning: "Eurostar services between the UK and the Netherlands are severely disrupted following a fire near Rotterdam Central station.
"Eurostar has advised they expect trains to be disrupted until at least 6 July 2026. Travel times are expected to be significantly longer due to trains having to take alternative routes due to fire damage and trains between London and Amsterdam will not stop in Rotterdam.
"If you are planning to travel between the UK and the Netherlands, check the latest information with your travel operator before you travel and the latest updates on the Eurostar website."
