GO Transit says staffing shortages caused by the Omicron variant of COVID-19 have prompted cancellations over the holidays, with additional service reductions planned in the coming days.

The regional transit agency serving the Greater Toronto and Hamilton region says a temporary reduction in train and bus service is set to begin within days, and new schedules will be made available at that time.

It says cancellations will be spread across its seven train corridors and bus routes, but notes cancelled trains will not be replaced by buses.

GO Transit says frontline teams are averaging 20 to 30 per cent fewer staff each day because of illness or isolation, and that rate is expected to rise over the next few weeks.

The agency says the service reductions will be temporary.

On Wednesday, the GO Transit site showed five cancelled train trips.

“We know this challenging situation is temporary until we're through this wave of the pandemic, but we really appreciate our customers' understanding and patience,” spokeswoman Anne Marie Aikins said in a statement.

This report by The Canadian Press was first published Jan. 5, 2022.