An incident at Southern Cross station has caused significant delays across the city

Significant delays have hit eight train lines across Melbourne, with waits of up to 40 minutes, after an incident at Southern Cross.

An incident at the Southern Cross Railway station has delayed trains across Melbourne.

Train lines have been delayed across Melbourne after a man climbed onto a track at the Southern Cross station early on Monday.

Emergency services were called to the railway station following reports of the man on the tracks about 6.20am.

He was not injured but has been taken to hospital for assessment.

Police are investigating the circumstances surrounding the incident.

Delays of up to 40 minutes are to be expected on the Craigieburn, Sunbury, Upfield, Werribee and Williamstown lines.

The Cranbourne, Frankston and Pakenham lines will run direct to and from Flinders St to avoid the city loop stations.