Federal prosecutors in Manhattan on Monday accused a Russian tycoon of scheming to make $1 million in illegal campaign donations to federal and state political candidates in the United States to gain favorable licensing decisions for a cannabis business venture.The prosecutors said the donations by the businessman, Andrey Muraviev, 47, were at the heart of an illegal campaign finance scheme conducted in the months before the 2018 midterm elections that also involved two Soviet-born businessmen, Lev Parnas and Igor Fruman, and two other co-defendants.Mr. Parnas and Mr. Fruman were allies of Rudolph W. Giuliani, former President Donald J. Trump’s personal lawyer, and assisted Mr. Giuliani in his efforts to undermine Joseph R. Biden Jr. when he was a leading Democratic presidential candidate.The allegations against Mr. Muraviev are not new; his name and alleged role surfaced at the October trial of Mr. Parnas and a co-defendant, Andrey Kukushkin, who were convicted of conspiring to funnel Mr. Muraviev’s money to American political candidates to aid their marijuana business plan.The indictment unsealed on Monday charges Mr. Muraviev with making political donations as a foreign national in the name of another person, as a so-called straw donor. A second count accuses him of conspiring to do so.Mr. Muraviev is believed to be in Russia and remains at large, the prosecutors said. Each of the two counts against him carries a maximum sentence of five years in prison, the government said.“He attempted to corrupt our political system to advance his business interests,” Damian Williams, the U.S. attorney for the Southern District of New York, said in a statement. He said his office was “committed to rooting out efforts by foreigners to interfere with our elections.”Prosecutors also said in a court filing on Monday that the indictment against Mr. Muraviev was returned by a federal grand jury in September 2020, and they gave no explanation as to why the unsealing of the charges did not occur until this week.The timing of the unsealing of the indictment drew sharp criticism from the lawyer for Mr. Kukushkin, who is to be sentenced on Tuesday.The lawyer, Gerald B. Lefcourt — noting in a letter to the court that the government news release announcing the charges described Mr. Muraviev as a “Russian oligarch” — accused prosecutors of an “obvious publicity stunt and orchestrated effort to manipulate Mr. Kukushkin’s sentencing proceedings.”In a brief phone interview, Mr. Lefcourt said the government had timed the unsealing of the charges “to exploit the feelings of outrage” against President Vladimir V. Putin of Russia in hopes of influencing the judge, J. Paul Oetken, who will sentence Mr. Kukushkin.Mr. Lefcourt also noted that the indictment does not use the word “oligarch” to describe Mr. Muraviev but calls him a “Russian citizen and businessman.”He said his client, Mr. Kukushkin, was from Odessa, Ukraine, “and he’s acting as best he can to support Ukrainian refugees and his friends from Odessa, doing everything he can.”Nicholas Biase, a spokesman for the Southern District, declined to comment on Mr. Lefcourt’s statements.The charges against Mr. Muraviev come as the United States and its allies continue to seek to punish Russia financially for its war on Ukraine. Earlier this month, the Justice Department announced a new task force to “hold accountable corrupt Russian oligarchs” who had supported the invasion.