LNER is carrying out a major update to the route - which runs between London and Edinburgh, via Yorkshire and the East Midlands - so it can "deliver quicker, more reliable services for passengers".
LNER has been running a reduced long-distance service recently, but that has now ended ahead of this weekend's disruption.
There will be no LNER trains running to or from London Kings Cross from lunchtime today (June 4) until Sunday (June 6), and there will be no trains to or from St Pancras International via Finsbury Park between today (June 4) and Sunday (June 6).
However, trains will still be running to London from Hull via Hull Trains, albeit on a reduced and amended timetable.
Hull Trains said: "Major engineering works are taking place in the London King's Cross area as part of the East Coast Upgrade. Hull Trains will be operating a reduced and amended service to/from London St Pancras with extended journey times."
Advice on the LNER website says: "Significant disruption with LNER services terminating at Peterborough and St Neots on Friday 4 June and no LNER services south of Grantham on Saturday 5 or Sunday 6 June. There will also be no trains to/ from London King’s Cross Station or to/ from London St Pancras Station via Finsbury Park.
- Substantial planned disruption due to works to complete the installation of a new tunnel at Werrington, north of Peterborough, and to complete track and platform work at London King’s Cross. These upgrades will improve reliability and allow faster acceleration and deceleration of our Azuma trains.
- After 1400 on Friday 4 June, those choosing to travel will need to transfer at St Neots for rail replacement services to Bedford for Thameslink services to London St Pancras International.
- On Saturday 5 and Sunday 6 June, those choosing to travel will need to transfer at Grantham for rail replacement services to Corby for East Midlands Railway services to London St Pancras International. On Sunday 6 June, some rail replacement services will connect to and from Kettering as opposed to Corby. Please check your journey.
- Rail replacement journey times will be substantial.
- There will be no connecting rail replacement journey from Grantham towards London after 2200 on Sunday 6 June.
- There will also be no connecting trains between Melton Mowbray and Peterborough from Friday 4 to Sunday 6 June.
- Overall journey times will be significantly longer and should be avoided wherever possible.
- Alternative routes will likely be very busy and should also be avoided. There is also major engineering work on the West Coast Mainline, more details on the National Rail Enquiries Future engineering work page.
- Station specific travel advice is available at www.EastCoastUpgrade.co.uk.
- If you need to travel you can create a Ticket Alert for these dates.
- You must have a seat reservation to travel on LNER trains