As Federal Reserve Chair Jerome H. Powell and Treasury Secretary Steven Mnuchin scrambled to save faltering markets at the start of the pandemic last year, America’s top economic officials were in near-constant contact with a Wall Street executive whose firm stood to benefit financially from the rescue.

Laurence D. Fink, the chief executive of BlackRock, the world’s largest asset manager, was in frequent touch with Mr. Mnuchin and Mr. Powell in the days before and after many of the Fed’s emergency rescue programs were announced in late March. Emails obtained by The New York Times through a records request, along with public releases, underscore the extent to which Mr. Fink planned alongside the government for parts of a financial rescue that his firm referred to in one message as “the project” that he and the Fed were “working on together.”

While some conversations were previously disclosed, the newly released emails, together with public calendar records, show the extent to which economic policymakers worked with a private company as they were drawing up a response to the financial meltdown and how intertwined BlackRock has become with the federal government.

60 recorded calls over the frantic Saturday and Sunday leading up to the Fed’s unveiling on Monday, March 23, of a policy package that included its first-ever program to buy corporate bonds, which were becoming nearly impossible to sell as investors sprinted to convert their holdings to cash. Mr. Mnuchin spoke to Mr. Fink five times that weekend, more than anyone other than the Fed chair, whom he spoke with nine times. Mr. Fink joined Mr. Mnuchin, Mr. Powell and Larry Kudlow, who was the White House National Economic Council director, for a brief call at 7:25 the evening before the Fed’s big announcement, based on Mr. Mnuchin’s calendars.

book on funds.

On March 24, 2020, the New York Fed announced that it had again hired BlackRock’s advisory arm, which operates separately from the company’s asset-management business but which Mr. Fink oversees, this time to carry out the Fed’s purchases of commercial mortgage-backed securities and corporate bonds.

BlackRock’s ability to directly profit from its regular contact with the government during rescue planning was limited. The firm signed a nondisclosure agreement with the New York Fed on March 22, restricting involved officials from sharing information about the coming programs.

were contracting and its business outlook hinged on what happened in certain markets.

While the Fed and Treasury consulted with many financial firms as they drew up their response — and practically all of Wall Street and much of Main Street benefited — no other company was as front and center.

Simply being in touch throughout the government’s planning was good for BlackRock, potentially burnishing its image over the longer run, Mr. Birdthistle said. BlackRock would have benefited through “tons of information, tons of secondary financial benefits,” he said.

Mr. Mnuchin could not be reached for comment. Asked whether top Fed officials discussed program details with Mr. Fink before his firm had signed the nondisclosure agreement, the Fed said Mr. Powell and Randal K. Quarles, a Fed vice chair who also appears in the emails, “have no recollection of discussing the terms of either facility with Mr. Fink.”

“Nor did they have any reason to do so because the Federal Reserve Bank of New York handled the process with great care and transparency,” the central bank added in its statement.

Brian Beades, a spokesman for BlackRock, highlighted that the firm had “stringent information barriers in place that ensure separation between BlackRock Financial Markets Advisory and the firm’s investment business.” He said it was “proud to have been in a position to assist the Federal Reserve in addressing the severe downturn in financial markets during the depths of the crisis.”

The disclosed emails between Fed and BlackRock officials — 11 in all across March and early April — do not make clear whether the company knew about any of the Fed and Treasury programs’ designs or whether they were simply providing market information.