Rail passengers on the East Coast Main Line have been “strongly advised” not to travel to Kings Cross on October 17 and 18 while work continues on a £1.2 billion upgrade.

St Neots LNER services to and from the north will provide start and stop services, with buses running to Bedford where passengers can use Thameslink and East Midlands Railway to St Pancras and there will be no Great Northern or Thameslink services into Kings Cross, Moorgate or St Pancras International via Finsbury park, with limited replacement bus services.

Network Rail and train operators said the East Coast Upgrade would transform journeys between London and the north, enabling more services on the mainline necessary to meet passenger demand and create a more reliable railway - but essential work on the signalling system could only take place when trains were not operating.

There has also been a warning that more services will be disrupted into the new year as the work continues.

A LNER spokesman said: “Passengers are strongly advised not to travel to or from London over the weekend.

“Those who have an essential need to do so should check their journeys via National Rail Enquiries, at EastCoastUpgrade.co.uk or with their train operator.

“They should also allow plenty of time as replacement services are expected to be busy. Passengers are reminded that they must wear a face covering on public transport, unless they are exempt, or they could be fined up to £3,200.”

The operators added: “Further work is planned over the coming months, including another weekend closure at London King’s Cross over the weekend of November 21/22 and an extended closure between Christmas and the new year.

“On Saturday 17 and Sunday 18 October we need to make changes to the signalling and power lines, and we can only do that by stopping trains coming in and out of the station. We’re advising people not to travel to London over the weekend, but those who do need to should check their journeys via National Rail Enquiries, at EastCoastUpgrade.co.uk or with their train operator and allow plenty of time.”