An LNER spokesman said the disruption is expected to last until this afternoon.
A replacement coach service will be available from Alnmouth to Berwick and from Berwick to Dunbar and Edinburgh.
Other trains affected include the Kings Cross to Edinburgh trains, Stirling to Kings Cross and Leeds to Aberdeen.
Alternative road transport will be provided.
For more information visit the LNER website.
A LNER spokesman said: “We are sorry for the inconvenience this may cause to your journey today. If your journey has been delayed you may be entitled to some compensation. Find out more about our Delay Repay scheme at lner.co.uk/delay.
“Follow us on Twitter at @LNER for the latest Travel Updates.