The deputy mayor for economic development, Daniel Doctoroff, said yesterday that putting off a decision on whether to build the proposed West Side stadium until a host city is chosen for the 2012 Olympics would be “a tragic mistake.”

Mr. Doctoroff, who appeared at a press conference to announce the details of a visit by the IOC’s evaluation commission, which will arrive a week from Sunday, made the remark in response to comments last week by state Senate Majority Leader Joseph Bruno, a Republican, and Assembly Speaker Sheldon Silver, a Democrat. Mr. Bruno and Mr. Silver had said it would be best to postpone a decision on whether to build a stadium over the West Side rail yards until after the IOC announces the winning city in Singapore on July 6.

“With all due respect to Senator Bruno and Speaker Silver, I’ve been spending a lot of time over the last year and a half with IOC members … and what is probably the single most important factor in the vote is their belief that the people they hope to partner with can deliver on their promises. They are not going to vote for us unless they believe that on the single most important venue, we will be able to deliver.

“I know that people say in the past no one’s ever started construction [on an Olympic stadium] before the selection, but it ignores several critical facts,” he said. “The first is that we are in, by far, the single most competitive race of all time. We’re competing against four world cities, three of whom already have Olympic stadiums. In addition, we are competing in a post-Athens environment, while although the games turned out to be spectacular, it was after seven years of nervousness, of stress, because it wasn’t clear everything was going to get done, and therefore, the standards that have been imposed on bid cities is much greater.”

The city had hoped to secure approval for the Jets stadium, known officially as the New York Sports and Convention Center, by the time the evaluation commission arrived in the city. But the Public Authorities Control Board has yet to approve the plan, and the Jets and the Metropolitan Transportation Authority have a tentative agreement to enter into nonbinding arbitration before a former U.S. senator, George Mitchell, to reach a price for rights to build on the West Side rail yards. Meanwhile, Madison Square Garden, in an offer opponents say was designed to scuttle the stadium, offered the MTA $600 million for the waterfront parcel.

Of the Madison Square Garden bid, Mayor Bloomberg said at a separate event yesterday, “You’ve got one company that says New York City has been picked by the rest of America to represent them and go to the world and say, ‘Let us host the Olympics,’ and this company says, ‘To hell with all of America. We don’t care. We’ve got a monopoly and we’re going to try and keep it.’ “

The mayor added that it was important to get the Jets stadium built now, rather than wait until after the IOC’s July vote.

“We have to get it going now for two reasons. One, because without that we have no chance to get the Olympics, but, two, we have to get it going now because we need the jobs now. And if somebody says, ‘Well, let’s wait and see if we get the Olympics, or I’ll approve it conditional on getting the Olympics,’ that doesn’t do us any good.”

Next week’s visit by the IOC will be the first and only one to the city. The privately financed group NYC2012 is spending $1 million in cash and $2 million of in-kind donations to woo the 16-member committee.

“We are seven days from the biggest single test we have faced thus far,” Mr. Doctoroff said. “For four-and-a-half days next week, New York will pull out all of the stops.”