Virgin Trains urge passengers "not to travel between Scotland and England" after a tree falls on the tracks between Carlisle and Lockerbie
The rail company has advised passengers to seek refunds rather than travel after a fallen tree blocks the lines north of Carlisle.
Engineers for Network Rail, which manages the UK's rail infrastructure, are currently attempting to repair the damage at Floriston in Cumbria.
The disruption to the West Coast main line follows an earlier incident this morning on the East Coast main line - the two rail routes in and out of Scotland.
While emergency services have said that the incident on the East Coast line is now cleared, major delays and cancellations remain in place.
Virgin Trains, who operate the West Coast line, have advised that passengers can use their tickets to travel later today or tomorrow or get a full refund.
They insist that because of the disruption on the East Coast Main Line, it is currently not possible for passengers to use this route as an alternative.
A spokesperson for Virgin Trains said: “The closure of our route to Scotland is causing significant disruption and we want to apologise to all our customers affected by this. We’re doing our best to help people complete their journeys but would advise anyone who has not set off on their journey to either wait until the disruption has cleared, travel tomorrow or get a refund.”