White House national security adviser Richard V. Allen denied yesterday that he had ever initiated or discussed the $1,000 honorarium he received as thank-you money from Japanese journalists for an interview with Nancy Reagan.

In a brief written statement, Allen said: "As to whether I asked for or ever expected to receive any honorarium, gratuity or fee, the answer is categorically 'no.' Nor was such a matter ever raised with me by anyone at any time."

But Allen did concede for the first time that he had fielded the initial request for the interview, which he said he "passed to others for evaluation, handling and decision."

Meanwhile, National Security Council staff sources said that Allen had continued to use the office where the $1,000 was found in a safe as a second, "hideaway" office, despite White House assertions that he had not used the office since the first days of the administration.

Allen's statement said that the request for the Reagan interview came from "the wife of a friend of many years' standing," whose husband had been Allen's academic colleague and later, like Allen, a consultant to several Japanese businesses and organizations. Allen said that while they are friends, he has never had a financial relationship with the man.

Allen did not elaborate on either his role in the interview arrangements or the identity of the person who requested the interview.

However, a White House official confirmed that the intermediary was Chizuko Takase, wife of Tamotsu Takase, whom Allen met in the 1960s at the Hoover Institution at Stanford University.

Yesterday, Washington Post correspondent Tracy Dahlby reported from Tokyo that a representative of Shufu no Tomo, the Japanese women's magazine that conducted the interview, said the magazine had been asked "by the person who arranged the interview what we were thinking about in terms of 'gratitude,' " and that the magazine's editors had replied that they planned to offer a $1,000 honorarium.

It was this money whose receipt Allen acknowledged on Friday. He said Japanese journalists handed it to him in an envelope the day after President Reagan's inauguration, when the interview took place.

Allen said Friday that he had instructed a secretary to put the money in a safe in his office in the Executive Office Building. Soon after, he moved out of that office and into quarters in the White House West Wing, he said, and forgot all about the money left behind.

However, NSC staff sources said yesterday that Allen continued to use that office on the third floor of the Executive Office Building. He has maintained a desk there, the sources said, and used the room as a larger, quieter place to work alone and meet with foreign dignitaries.

When Allen was not using this office, other NSC staff members used it on occasion for meetings and special projects. One NSC official said that military aides who worked there most recently knew about Allen's safe but not what was in it.

On Friday, David Gergen, White House assistant for communications, said in response to a question that the office was not a "hideaway office type of thing" for Allen but "is occupied by three members of the staff."

Gergen had first said that the Justice Department had concluded that Allen had done nothing wrong and that the case was closed. But later in the day, Gergen said that the investigation had apparently not been closed and that White House counsel Fred Fielding had prepared a statement giving Allen a clean bill of health without checking with Justice or the FBI.

White House officials spent much of yesterday trying to sort out facts and strategy. They decided to say nothing beyond a two-sentence statement. It read:

"On Friday, in response to urgent requests from the press, the White House provided information available to it relating to Richard Allen and the handling of funds from the Japanese magazine Shufu no Tomo. In view of the fact that the Justice Department continues to have the matter under review, the White House will refrain from additional comment on this subject."

The involvement of the wife of Allen's longtime friend, Takase, in arranging the interview clarifies how a Japanese magazine that is relatively obscure in the United States could score such an exclusive early interview with the first lady.

Before joining the administration, Allen was a consultant to several Japanese concerns through his Potomac International Corp. here.

Last fall, the disclosure of Allen's past relationship with Takase thrust the final days of Ronald Reagan's presidential campaign into a fitful crisis when the Wall Street Journal alleged in a front-page article that Allen had supplied Takase with confidential trade data in 1970.

The period in question was after Allen left his job as a senior assistant on the NSC staff in the Nixon administration, but while he was on the President's Commission on International Trade and Investment Policy.

In letters, Allen urged Takase to use his influence with Japanese government officials to set up a large and sophisticated Japanese lobby on Capitol Hill to fight what Allen warned was a growing protectionist movement.

In one letter, Allen told Takase that "no commissioner may discuss with the press the matters before the commission." In that letter and in subsequent ones, however, Allen disclosed confidential information.

He defended his actions by saying that the information was widely circulated to other lobbyists and academicians in Washington.

Nevertheless, Allen briefly stepped down as Reagan's foreign policy adviser because of the political flap created by the article.

Since joining the Reagan administration, Allen has continued his contacts with Takase, The Washington Post has learned. Takase visited the White House in March during sensitive staff deliberations on seeking voluntary export restraints on Japanese auto manufacturers, according to a source who accompanied the party to the White House. Takase escorted Shoichiro Toyoda, the executive vice president of the Toyota auto manufacturing company..

According to the source, Allen prevented a State Department representative from accompanying Takase and Toyoda into the White House. The State Department representative was left literally standing at the White House gate.

After the visit, Takase returned to Japan and told a conference of U.S. and Japanese corporate officials and consultants in April about his visit with Allen.

According to a Washington consultant who took notes on Takase's address, Allen reported to Toyoda and Takase that the White House policy makers were committed free traders.