State Senator Malcolm A. Smith, who has been charged in a plot to bribe his way onto the ballot to run for mayor of New York City, asked a judge recently to delay his corruption trial for a very practical reason: It would interfere with his re-election campaign.

But the office of Preet Bharara, the United States attorney for the Southern District of New York, said in a court filing on Friday that it opposed the request to push back the tentative trial date in early June.

Mr. Smith’s request “frustrates the public’s interest in a timely resolution of the pending criminal charges,” Mr. Bharara’s office told Judge Kenneth M. Karas of United States District Court in White Plains.

Image Senator Malcolm A. Smith Credit... Frank Franklin II/Associated Press

The office added that Mr. Smith was not claiming that failing to delay the trial would “in any way impact his ability to defend himself.”