The rush to build Vancouver's new convention centre, which will be home to the media during the 2010 Winter Olympics, has caused the project's costs to skyrocket.

The government-funded facility was initially expected to cost C$495 million, but the estimate has been raised several times and now stands at C$883 million (£446 million) -- a price tag that British Columbia's auditor general warned may rise again.

The facility being built over the water on the city's harbor will be the headquarters for international broadcasters and other media during the Games, but the government does not consider it part of the C$1.6 billion budget for hosting the event and building sports venues.

The project adds to existing facility on the harbour. Plans for the convention centre were announced in 2002, while Vancouver was still bidding for the Winter Games.

The provincial government then agreed the facility would be ready in time for the Olympics.

The initial announcement by provincial and federal officials to spend C$495 million on the project was made before detailed cost estimates had been completed, and the budget has since been buffeted by inflation and design changes, the auditor's report said.

The decision to speed up work and complete it well before the Olympics begin has pushed up the cost of purchasing for the project, and a fixed-price contract with the construction firm was not signed until this year, according to the report.

The Vancouver Convention Centre Expansion Project said in its response to the report that it remains confident it can stay within the C$883 million budget that was last updated by the provincial government in July.

The Vancouver Organizing Committee, which is not responsible for the convention centre's construction, has said the Olympic sports venues remains on budget and on time.

Reuters