The upcoming G8 and G20 summits will likely be remembered as the most expensive ever held, but the parliamentary budget office says it's too early to tell whether the estimated $930 million in security is being well spent.

It's difficult to compare the price tag to previous events because host governments tend to avoid releasing their full cost, and because there have been too few similar events, according to a report released on Wednesday by Parliamentary Budget Officer Kevin Page.

The report also found that the cost to hire each RCMP officer has quadrupled since the 2002 G8 summit in Kananaskis, Alta., while the cost of hiring each Canadian soldier has tripled over that time.

Alfonse MacNeil, the RCMP's chief superintendent and the head of security for the G8 and G20 summits, said that holding the two events in separate locations contributed to the hefty price tag.

"We have had to duplicate the security forces in Toronto and in Huntsville," he said, adding that "there is no question there would have been some saving" had the events been held at the same venue.

Allan Bell, president of private security firm Globe Risk Holdings International, concurred.

"It would have been one fence, it would have been one set of security as opposed to having two separate locations with different logistics and administration problems," he said on CTV's Power Play.

Another reason for the high cost is that public figures who have been invited to attend will attract security problems that Canadian cities would not otherwise have to contend with.

"Each one of these leaders has their own risks, their own problems and their own threat levels, which we have to deal with," Bell said. "So we have to be prepared for the worst."

The overall cost for the back-to-back summits, which are being held June 25-27, is projected to be $1.2 billion.

The Harper government has been criticized for the 10-digit expenditure, which includes $1.9-million on a media pavilion to promote Canada.

The Liberals have accused the Conservatives of spending a large portion of the $50-million G8 fund on projects that are unrelated to the summit in Huntsville.

The local member of Parliament, Industry Minister Tony Clement, accused the Liberals of "twisting the facts" and the Tories say that spending on the events is justified.

The spending controversy has caught international headlines.

With files from The Canadian Press