President Anwar Sadat, ignoring the reluctance of other nations to send high-level representatives to the shah's funeral, today organized solemn but lavish rites to honor the shunned Mohammad Reza Pahlavi.

The Egyptian government had sounded out other nations about the possibility of gathering numerous high-level delegations in Cairo, but was made to understand that such invitations would be embarrassing, a ranking Foreign Ministry official said.

The United States has delegated Ambassador to Cairo Alfred Atherton to represent Washington at the funeral.

Sadat's decision to bury the deposed Iranian "king of kings" with full military pomp befitting a head of state dramatized his determination to pay a last public tribute to his friend and former benefactor, despite the awkward reluctance shown by most of the nations that once were the shah's closest allies.

The exiled Pahlavi died yesterday inCairo of complications resulting from his cancer treatments.

Former U.S. president Richard Nixon, who arrived tonight on a regular commercial flight to attend the ceremonies on his own, criticized the Carter administration in particular for what he said was its failure to stand by the shah as a friend in need during his fall from power and subsequent 18 months of exile. "I think the treatment of the shah by the administration after he left [Iran] was shameful," Nixon told reporters after an official reception with flag and honor guard at Cairo Airport. "And I think President Sadat's guts in providing a home for the shah in his last days at a time when the U.S. turned its back on one of its friends is an inspiration to us all."

Nixon, accompanied by his son-in-law Edward Cox, was the most prestigious foreign dignitary to show up for the funeral today. The former king of Greece, Constantine, was reported on his way, and King Hassan of Morocco sent his minister of royal courts, Mulay Alawi.

Most nations, apparently fearful of upsetting the new Islamic government in Iran, planned to be represented at the maximum by their ambassadors in Cairo. President Carter, who oncelifted a New Year's eve champagne toast in the shah's palace library in Tehran, delegated Atherton to convey condolences to the shah's widow, empressFarah.

[In Washington the State Department, after a day of silence and behind-the scenes consultations, confirmed that Atherton would also represent the United States at the funeral and that the administration did not plan to send any other official representatives to Cairo.]

[State Department spokesman John Trattner said Nixon's attendance at the funeral has "no connection with this administration." He said the administration is "not concerned" about Nixon's presence at the funeral, and he declined to comment on Nixon's charge that the administration's treatment of the shah would be remembered as "one of the blackest pages" in the history of American diplomacy.]

As for Moslem nations, Sadat already had declared in a televised address marking the shah's death yesterday that he would not invite their leaders. When he welcomed Pahlavi and his family last March, the Egyptian leader was criticized widely by fellow Arab and Moslem leaders sympathetic to the Islamic revolution that dethroned the shah.

Sadat defied their criticism then, as he is defying the embarrassment of the shah's former friends now, by citing the Islamic virtures of hospitality and friendship. In keeping with the religious tone of his gesture, the funeral plans as outlined by Egyptian officials put strong emphasis on Islam.

The shah's body, which has been in the Maadi Military Hospital since his death at 9:50 a.m. yesterday after a six-year struggle with cancer, was to be transferred tonight to the Abdeen presidential headquarters in central Cairo. There the body was to lie in state in a closed coffin in the main hall, draped with an Iranian flag and guarded at each corner of the coffin by formally attired officers from Sadat's own presidential guard.

Funeral plans called for Sadat and his family, accompanying the family of the shah, to gather around the coffin and read silently from the opening chapter of the Koran, the Moslem holy book.

"In the name of God, he who makes mercy, the merciful," it begins. "Praise be to God, the lord of the earth, he who makes mercy, the merciful, the king of the day of judgment."

From there the mourners were to take their places behind a caisson bearing the shah's body in a procession to be Rifai Mosque, about a mile away. Sadat gave orders for three generals and one admiral to walk at each corner of the caissonborne coffin, carrying the medals and decoration that the shah had accumulated during his years as absolute ruler of Iran.

Ahead of them will march more than 1,000 officers from each section of the armed forces and the presidential guards, including a military band and wreath bearers, officials from the presidential palace said.

A Shiite Moslem clergyman will lead prayers when the solemn procession reaches the 19th-century Rifai Mosque, where the shah's body is to be entombed behind a marble wall in the same room where his father was buried briefly during World War II before being returned to a shrine in Iran.

Also buried in the 60,000-square-foot limestone mosque, in the shadow of Saladin's citadel on the heights of Cairo, are the last two kings of Egypt, Farouk and Fuad, along with Fuad's mother, Sadat and the shah's family planned to stand alongside the towering building and receive condolences after a 21-gun salute as the body is lowered into its tomb and three more volleys as the final resting place is sealed.

Egyptian officials declined to reveal which members of the shah's family would take part in the ceremony, citing fears for their safety during the funeral procession along a broad street through one of Cairo's most crowded neighborhoods.

Along with Farah and her four children, the shah's twin sister Ashraf was seen in Cairo yesterday. Also here is Ardeshir Zahedi, the former Iranian ambassador to Washington who was close to the shah during his reign and remained in close touch during his exile.