It comes after a fault was discovered on the railway line, according to Southern Rail.
A statement on X (formerly Twitter) at 4.40pm read: “Due to a points failure between Hastings and Ashford International, services are unable to run in either direction.
“Services scheduled to call between Eastbourne and Ashford international will only operate between Hastings and Eastbourne.”
In an update at 5pm, Southern wrote: “Please delay your travel until later as there is no alternative transport available at present.
“We have requested rail replacement buses and are waiting on confirmation from our suppliers.”