Former president Nixon told President Reagan about his plans to visit four other Arab nations after attending Egyptian President Anwar Sadat's funeral, but Reagan did not pass the information to his senior staff members, White House spokesmen said yesterday.

Deputy White House press secretary Larry Speakes said a report in The Washington Post Monday erred in saying that Nixon had not informed Reagan of his travel plans.

Asked if Reagan had forgotten to mention the plans to anyone after being told by Nixon Oct. 8, White House deputy chief of staff Michael K. Deaver nodded affirmatively.

At the same time, State Department spokesmen denied The Post's report that Secretary of State Alexander M. Haig Jr. had helped arrange Nixon's trip without telling the White House.

State's denials were consistent on that point but differed in detail. Department spokesman Dean Fischer first told reporters that Nixon telephoned Deputy Secretary of State William P. Clark at 10 a.m. Oct. 8 about the trip and that Clark relayed word to Deaver.

Deaver said he could not recall such a phone call, and Fischer later said he had misunderstood.

Meanwhile in Washington, Fischer's deputy, Alan Romberg, said that Clark told Haig of Nixon's plans at the State Department Oct. 8 before Haig left for Cairo and that Haig instructed a staff person to inform the White House. Romberg was not sure that the staff person did so.

Fischer said ambassador-at-large Vernon Walters helped Nixon aide Nicholas Ruwe make arrangements for Nixon's trip to Saudi Arabia. Other sources said Ruwe asked Walters' help in arranging Nixon's visit to Morocco. Nixon also visited Jordan and Tunisia.

Ruwe said that Nixon and Haig first discussed the trip by phone Oct. 7 but that Nixon was not definite then about his travel plans. Ruwe said Nixon was trying to keep word of his trip quiet in order not to distract from the Sadat funeral.

Joseph Canzeri, presidential assistant in charge of logistics of the funeral trip, told the Associated Press yesterday that "the first knowledge I had that Mr. Nixon was not going to return was when we got to the airplane."