Commuters in Melbourne have been warned to expect major delays on Wednesday when more than 800 bus drivers at two of Victoria‘s biggest bus companies go on strike.

Transport Workers Union (TWU) members employed by Dysons Group and CDC Victoria will strike for 24 hours as part of planned industrial action over improvements to pay, rostering and safety.

The strike follows months of failed negotiations, with the TWU demanding a deal that better recognises bus drivers and their importance within the community.

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“The current offers from CDC and Dysons fall short. Our members have been patient, but that patience has run out,” TWU Victorian/Tasmanian director of organising Sam Lynch said.

“It’s time for CDC and Dysons to stop dragging their feet and start listening to workers’ calls for respect and a fair day’s pay.”

Dysons said it was disappointed with the union members’ decision to strike given its recent proposal to improve wages and benefits for bus drivers, including a 9 per cent year-one wage increase.

“Industrial action, if carried out, will cause unnecessary inconvenience to public transport bus passengers,” it said.

“Dysons is working closely with the Department of Transport and Planning to minimise disruption to our passengers and valued customers, should this action proceed.”

CDC said it was committed to negotiating with the TWU “to reach a fair and reasonable resolution”.

According to the transport department, if the strike goes ahead as planned about a quarter of Melbourne’s 400 bus routes could be impacted.

Commuters have been warned to expect major delays on routes in Melbourne’s north and west, as well as in Ballarat, Mildura and Geelong.

Bus routes operated by Dysons across Melbourne will run to a Saturday timetable.

There will be no Dysons services on routes 301 Reservoir to Latrobe Uni express, 389 Mernda Station to Doreen Loop and 546 Heidelberg Station to Queen Victoria Market/Melbourne Uni.

School services on all Dysons routes will continue to run.

CDC Victoria will only operate school services from its depots in Oakleigh, Tullamarine, Sunshine and Mildura.

“Passengers on affected routes should consider other transport alternatives on Wednesday,” the transport department said.

Normal timetables should resume on Thursday.