WATERLOO, Ont. -- BlackBerry is selling the majority of its commercial real estate holdings in Canada, but the struggling smartphone maker refused Tuesday to say how much it expects to make from the deals.

Waterloo, Ont.,-based BlackBerry (TSX:BB) said it plans to use a combination of vacant sales and sale-leaseback arrangements in divesting the properties.

The company said the properties being offered for sale comprise more than three million square feet of space.

"BlackBerry will not comment on the potential value of a sale and will disclose further information as required in connection with any definitive sale transaction," it said in a release after markets closed.

The company is working with CBRE, a commercial real estate company that provides financing and management services in conducting the sales.

"BlackBerry remains committed to being headquartered in Waterloo and having a strong presence in Canada along with other global hubs," CEO and executive chairman John Chen said.

"This initiative will further enhance BlackBerry's financial flexibility, and will provide additional resources to support our operations as our business continues to evolve."

Shortly before Christmas, the University of Waterloo announced it had purchased five buildings and land from BlackBerry for $41 million.

The deal, which is expected to close Feb. 14, will add an additional 300,000 square feet and more than 1,000 parking spaces to the school's property holdings.

The university said it planned on using three of the buildings as soon as the deal closes, while the remaining two would be leased to the smartphone maker for up to five years.

BlackBerry pioneered the smartphone in 1999 and dominated the market for years but has since been eclipsed by Apple's iPhone as well as Android-based rivals.

Under new CEO Chen, the company has been working to turn around its business and last month entered into a five-year partnership with a Taiwanese company in an agreement that will offload much of its manufacturing costs.

On Monday, the company's shares rose more than eight per cent after it got a vote of confidence from the U.S. Defence Department, which said about 80,000 BlackBerrys would be deployed on its new mobile device management system by the end of the month.

The number represents about 98 per cent of the initial haul of devices, which includes another 1,800 devices like Apple's iPad, iPhone and tablets and phones on the Android operating system.

The disclosure last week also shows the U.S. government still considers BlackBerry part of its stringent security infrastructure.