Red Arrow is shutting down bus service starting Sunday until further notice.

The Calgary-based company, which has connected cities across Alberta for more than 40 years, said it felt the move was necessary to keep both passengers and staff safe and slow the spread of COVID-19.

"In these unprecedented times, we all struggle to make the right choice to protect as many people as possible," the company said in a statement posted to its website on Tuesday.

"Suspending a service like inter-city transportation is an extremely difficult decision, but we feel it is one we must now make."

John Stepovy, Red Arrow's director of business development, said the company has approximately 150 employees and about a dozen will be kept on to keep basic operations like its toll-free call centre running while the others will be temporarily laid off.

The company said it will resume service once government and medical authorities recommend it is safe to do so.

Red Arrow had scaled up its service in recent years to fill a void left by Greyhound's closure in 2018, which left some communities across the province with limited to no travel options.

After the outbreak started, the company enhanced cleaning and sanitization and limited the number of tickets sold on each bus to increase physical distancing, but Stepovy said it reached a point where the difficult decision to close down had to be made.

"For 40 years Red Arrow has gotten people safely home and now we're asking people to stay safely home," he said, adding that customers have largely supported the decision.

"As much of an inconvenience it may be for those that absolutely need the service to get access to medical care, or you know in many rural places it's access to staples, they understand."

Red Arrow's partner company, Ebus, has also suspended service in Alberta, but remains operating in B.C. for the time being. The Camrose Connector, a partnership between Red Arrow and the City of Camrose, has also been suspended.

Red Arrow serves Calgary, Edmonton, Camrose, Cold Lake, Fort McMurray, Grande Prairie, Lethbridge and Red Deer.

New Canada-wide restrictions for travel were introduced Saturday in response to the global novel coronavirus pandemic

Domestic travel by plane or train will no longer be allowed for any exhibiting signs of the illness, which include cough, fever and difficulty breathing, as of Monday. That ban does not apply to interprovincial bus travel.

As of Friday there were 542 cases of COVID-19 in Alberta.