The City of Winnipeg is in formal negotiations with Canada Post about purchasing its downtown building.

The post office uses its current location at 266 Graham Ave. as a mail processing plant. But it is moving those operations to new a facility near the airport in the summer of 2010.

The Winnipeg Police Service believes the Graham Avenue plant would be able to house its core functions in a way the current headquarters in the Public Safety Building cannot.

The limestone-clad exterior of the Public Safety Building is crumbling, while the interior of the downtown building — which also serves as the communications centre for the police, fire and paramedic services — no longer accommodates all of the needs placed upon it.

Police officials say there's not enough office space or room to process people under arrest. Chief Keith McCaskill has also said the force needs a larger place to store evidence and a better forensics facility. The Canada Post location is also more conveniently located near the Law Courts Complex.

"A downtown location would allow us to increase our visible presence on the streets and in covered walkways and add to our ability to build relationships with merchants, workers and visitors to the downtown," said McCaskill.

If and when an agreement is met, the sale would be contingent upon a 120-day due diligence period.

During that time, the city would examine the property's suitability, perform a cost-benefit analysis in regard to converting it to a police headquarters, and look at any other relevant factors, according to a news release issued by the City of Winnipeg on Friday.

If the study of all these factors results in an administrative recommendation to purchase the property, a report would go to city council for a vote.