Recent performance figures show 84.9 per cent of trains ran on time in January, a 2.7 per cent drop from the previous month and the worst result on the Warrnambool train line since March 2019.

It's a bad start to the year, with that January result falling short of V/Line's punctuality target of 92 per cent for the seventh consecutive month.

The region's train service has exceeded that target just 12 times in the past decade.

Information received from V/Line revealed two major incidents impacted performance on the south-west corridor during January ,one involving a group of unruly passengers at North Shore, near Geelong, and a Victoria Police operation between West Footscray and Footscray train stations.

A V/Line spokeswoman said there were improvements in reliability across 10 of the 11 regional lines on December, including Warrnambool, despite ongoing protected industrial action taken by the Rail Tram and Bus Union (RTBU) on January 29, as well as a train fault.

Of the 228 Warrnambool services scheduled in January, 14 were cancelled.

"We understand delays are incredibly frustrating for our passengers and we continue to look for and trial ways to improve Warrnambool line service," she said.

It comes after Minister for Public Transport Infrastructure Jacinta Allan told The Standard that high-speed V/Locity trains would not run on the line once $114 million upgrade Warrnambool line upgrade was complete.

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