Sirhan B. Sirhan, the convicted assassin of Robert F. Kennedy, said in a "statement to the nation" today that he had always felt sorry for Kennedy's death and that he thought that if the senator were alive he would agree that Sirhan had suffered enough for his crime.

Sirhan should not be held beyond his scheduled 1984 release date, he told a three-member panel of the California Board of Prison Terms, because "two wrongs do not make a right." Kennedy would have been one of the first to argue that he should not be denied "equal treatment under the laws of this country," he said.

Sitting in a Soledad State Prison hearing room, Sirhan, 38, found himself once again the subject of world attention, nearly 14 years after he killed the senator as Kennedy sought the nomination for president of the United States. Fifty reporters recorded his every word off a closed-circuit television system piped into a makeshift press room 200 yards away as the panel considered whether to release Sirhan on Sept. 1, 1984.

Seven years ago a similar three-member board, feeling itself bound to treat Sirhan as any other first-degree murderer, granted him a 1986 parole date, later moved up to 1984 because of his apparently spotless prison record. The 16-year term would be three years longer than the average sentence served by first-degree murderers sentenced to life terms in the state.

But as the release date has neared and signs have appeared of the Palestinian-born Sirhan's lingering anger about his treatment in the United States, California citizens and officials have organized a massive campaign to rescind the parole date. The panel now considering Sirhan's parole has received 10,000 letters, telegrams and petitions protesting his release.

Testimony before the board focused on two threatening letters Sirhan wrote in 1971 and 1975 and other indications, in the view of the prosecution, that he might still be a threat to society if released.

At the same time, prison officials say, a smaller but significant number of letters have also come to them calling for the release of the man who indicated he shot Kennedy because of the senator's pro-Israel stance and who has become a household name in much of the Arab world.

The panel is expected to decide within two weeks.

"A political assassination should not be compared with the average murder because it tears at the very fabric of a democratic society," said Los Angeles County District Attorney John Van de Kamp, who forced the 10-day hearing that ended today to reconsider the parole date.

Deputy District Attorney Larry Trapp told the hearing in his final argument today that the board should consider two threatening letters from Sirhan that were not available to the 1975 board and should note other ill-tempered statements he has made since 1975 that indicate he is still dangerous.

Just this year, Trapp said, Sirhan told a staff member at this medium-security prison 120 miles south of San Francisco, "If my parole date is taken, I will turn the Arabs loose to get me out of prison, dead or alive."

"The issue is not whether I am liked or not but whether the laws of the country should be subverted as Mr. Van de Kamp suggests," Sirhan said in a firm, high-pitched voice as he read the appeal he had conceived, according to his attorney Luke McKissack, as a statement to the nation.

"I have spent agonizing and trying times on death row, where the question of life and living was in every thought. No person can feel better or richer in spirit for taking a person's life. When I get out, one of my interests will be to improve the quality of life.

"I sincerely believe that if Robert Kennedy were alive today he would not countenance singling me out for this kind of treatment. I think he would be among the first to say that no matter how horrible a deed I committed 14 years ago, that should not become the cause for denying me equal treatment under the laws of the country."

Sirhan spent much of his statement denying the testimony and magazine articles by other inmates who have suggested he had helped plan escapes from Soledad Prison or harbored other bizarre plans to steal plutonium for the Arab cause.

Sirhan was originally sentenced to death in the California gas chamber, but the state Supreme Court ruled in 1972 that the death penalty was unconstitutional and more than 100 convicted murderers on the state's death row received life sentences instead. Under state law, each was eventually entitled to a parole hearing and the 1975 board, although aware that their decision to grant Sirhan parole was controversial, did not appear to anticipate the eventual public outcry.

Van de Kamp's effort to delay Sirhan's release first emphasized alleged remarks by Sirhan to other prisoners that he planned to kill his victim's brother, Sen. Edward M. Kennedy (D-Mass.), and that he wanted to steal plutonium to help Libyan leader Muammar Qaddafi build nuclear weapons.

But other inmates belittled one of the anti-Sirhan witnesses, convicted murderer Lawrence Eugene Wilson, as a man willing to tell any story and a second witness disappeared when sought for arrest in connection with an armed robbery.

Among 30 witnesses heard in this hearing, the most significant testimony has been about two threatening Sirhan letters--one sent to his trial attorney, Grant Cooper, in 1971, and one sent to San Quentin prison official Vern Smith in 1975.

In the letter to Cooper, which began "Hey punk," Sirhan raged at his attorney and at Robert Blair Kaiser, author of the book "RFK Must Die": "If he Kaiser continues to talk about me like he's been doing on radio and TV--if he gets his brains splattered--he will have asked for it like Robert Kennedy did. Kennedy didn't scare me; don't think your Kaiser will. Neither of you is beyond my reach. Robert Blair Kaiser, RBK must shut his trap or die. Don't forget Cooper , you son-of-a-bitch, you are the one who cost me my life."

If the board decides to set aside the 1975 ruling in Sirhan's case, the convicted Kennedy assassin must be given a new parole hearing within six months. The board may then assign him a new parole date, or rule that he is still not suitable for release.