Natalia V. Veselnitskaya, the Russian lawyer who in 2016 met with Trump campaign officials in Trump Tower, was charged on Tuesday in a separate case that showed her close ties to the Kremlin.
Ms. Veselnitskaya, a pivotal figure in the investigation into Russian interference in the presidential election, was charged by federal prosecutors in Manhattan with seeking to thwart an earlier investigation into money laundering that involved an influential Russian businessman and his investment firm.
The money-laundering case was not directly related to the Trump Tower meeting. But a federal indictment returned in Manhattan seemed to confirm that Ms. Veselnitskaya had deep ties to senior Russian government officials and rekindled questions about whether the Kremlin tried to use her as an intermediary to Donald J. Trump’s campaign.
The charge stems from a 2013 civil investigation by the Manhattan prosecutors into the role that some of Ms. Veselnitskaya’s clients — Prevezon Holdings and its owner, Denis P. Katsyv — played in a scheme to launder ill-gotten money through New York real estate purchases.
The Justice Department asked the Russian government to assist its investigation, but the Russians refused, responding with a document that purported to exonerate Russian officials and Prevezon, according to the indictment.
The indictment said Ms. Veselnitskaya secretly cooperated with a senior Russian prosecutor in drafting the document, which was later filed in federal court in Manhattan.
She is charged with one count of obstruction of justice.
Ms. Veselnitskaya, 43, is believed to be in Russia, according to the United States attorney’s office for the Southern District of New York, which moved to unseal the indictment on Tuesday. The office gave no indication that it expected her to be sent to Manhattan to face charges.
Ms. Veselnitskaya did not respond to a request for comment on Tuesday. CNN quoted her as saying she had just learned of the indictment and would “defend her professional honor.”
That meeting is one focus of the investigation by the special counsel, Robert S. Mueller III, into whether the Trump campaign coordinated with Russia’s covert operation to sway the presidential race. It was organized after an intermediary promised that Ms. Veselnitskaya would deliver documents that would incriminate Hillary Clinton.
Last April, Ms. Veselnitskaya acknowledged in an interview with NBC News that she was not merely a private lawyer, but a source of information for the Russian prosecutor general, Yuri Y. Chaika. Now in Manhattan, prosecutors say she collaborated clandestinely with that office to write an official letter that benefited Prevezon.
For years, Ms. Veselnitskaya has been regarded as a trusted insider and go-to lawyer for the Moscow regional government.
In the fraud case, filed in 2013, the Manhattan prosecutors accused Prevezon and other defendants of using real estate purchases in New York to launder a small portion of the proceeds of a $230 million Russian tax scheme. The lawsuit was settled last May on the eve of trial for about $6 million, with Prevezon admitting no fault.
The Russian scheme had been uncovered by Sergei L. Magnitsky, the Russian lawyer who was imprisoned after exposing the scheme and who died in a Moscow jail.
Ms. Veselnitskaya has maintained that she was acting in a private capacity when she visited Trump Tower in June 2016, shortly after Mr. Trump clinched the Republican nomination.
Her claim has been undercut by revelations that the meeting was organized because campaign officials had been told she could offer damaging information about Ms. Clinton from the Russian government.
In addition, her memo on talking points for the meeting closely matched a memo Mr. Chaika’s office had prepared for an American congresswoman, incorporating some passages verbatim.
The indictment unsealed on Tuesday could further undermine Ms. Veselnitskaya’s story, alleging that a year before the Trump Tower get-together she worked hand in glove with Russian officials to derail the money-laundering case.
In that case, the Manhattan prosecutors alleged that corrupt Russian officials stole the corporate identities of companies owned by Hermitage Capital Management, a foreign investment firm operating in Russia, and used them to fraudulently claim $230 million in tax refunds.
As part of the investigation, the Justice Department asked the Russian government in 2014 for assistance in obtaining bank records and other materials pertaining to the fraud scheme, the indictment said.
In response, the Russians provided the supposed findings of an investigation that “purported to exonerate all Russian government personnel” and instead cast blame on the London-based chief executive of Hermitage, William F. Browder; his lawyer, Mr. Magnitsky; and others.
In 2015, lawyers representing Prevezon, which had been accused of laundering some of the fraudulent proceeds, filed court papers, including the declaration from Ms. Veselnitskaya, to argue that the Russian government’s findings were exculpatory evidence. The papers did not disclose her role, the indictment charged.
The indictment said Ms. Veselnitskaya exchanged emails with a senior Russian prosecutor, attaching drafts with edits and comments. Many of her suggestions “were adopted, either essentially verbatim, in rephrased form or with light edits,” it said.
The Russian prosecutor’s office did not respond to a request for comment.
Geoffrey S. Berman, the United States attorney in Manhattan, said on Tuesday that “fabricating evidence” in an attempt “to affect the outcome of pending litigation not only undermines the integrity of the judicial process, but it threatens the ability of our courts and our government to ensure that justice is done.”
Mr. Browder led a human-rights campaign against the Kremlin that has resulted in sanctions being imposed against Russian officials worldwide. He said on Tuesday that Ms. Veselnitskaya “came to the United States to disrupt the political process by lying about me and lying about Sergei Magnitsky, my murdered lawyer. And she got caught lying, and she’s being prosecuted for those lies.”