LONDON, SEPT. 28 -- It's been a heady and in some ways promising week for author Salman Rushdie. But the door to his invisible prison remains firmly locked, and friends and supporters concede the end of his 19-month-long ordeal is nowhere in sight.

Rushdie, a novelist who became a key figure in diplomatic relations between Britain and Iran, published a new book to generally favorable reviews this week. He also granted his first television interview since going into hiding in February 1989, and he watched hopefully as Britain and Iran resumed ties, broken 18 months ago after a death threat against him by Islamic fundamentalists.

But relations were restored without a prior commitment from Tehran to withdraw or publicly distance itself from the death threat issued by the late ayatollah Ruhollah Khomeini. Some critics fear that the British government no longer considers Rushdie's fate an important concern, a reflection of public hostility or general indifference to the Indian-born writer.

Rushdie, a British citizen of Moslem birth who has been in hiding under police protection, is "very hopeful" that the restored diplomatic ties may ultimately bring an end to his ordeal, according to Carmel Bedford, secretary of the International Salman Rushdie Committee here. But she said Rushdie is aware of the power held by fundamentalists in Tehran who support the death threat and may use it as a political tool in their struggle against moderates, such as President Ali Akbar Hashemi Rafsanjani.

"I'm sure Rafsanjani has got to tread very, very cautiously, and we have got to tread very, very cautiously," said Bedford. "It's still a long, slow process to reconciliation."

British Foreign Secretary Douglas Hurd held his first meeting with Iranian Foreign Minister Ali Akbar Velayati today at the United Nations, but the Rushdie affair was not raised, according to an official account of the session. Hurd said Thursday that the Iranians had promised not to interfere in Britain's "internal affairs," diplomatic code for not pursuing Rushdie.

The Independent newspaper called the diplomatic formulation "unduly and regrettably oblique," and critics said Tehran should, at the least, have withdrawn its offer to pay $3 million to any Iranian and $1 million to any foreigner who kills Rushdie.

In the television interview, to be broadcast here Sunday, Rushdie said his life under protective custody by Britain's Special Branch has "been hell." He has had to move clandestinely among safe houses and to avoid contact with family and friends, he said. He has sought to dodge Islamic hit squads, reportedly sent from Iran after Khomeini condemned as "blasphemy" Rushdie's novel, "The Satanic Verses."

"The book did not set out to be the thing it's been accused of being, which is insult and abuse," Rushdie said. "If that's how people have read it, if people have been upset in that way, then I'm sorry. . . . People have said I ought to be punished. All I can say is that if punishment is the aim, then I have had some."

Rushdie, 42, appeared relaxed during the interview, conducted at a secret location for London Weekend Television by Melvyn Bragg, a well-known television personality and friend of the novelist.

"Although there has been stress and it's been very alarming at times, the real problem is inside," Rushdie said. "It's torn apart everything I have ever thought about everything, which is probably not a bad thing for a writer, but this is a rather extreme way of doing it. . . . It's very strange to think that everything you think about everything has to be rethought."

Rushdie denied he had sought to damage the Moslem faith or those who follow it. "One of the greatest losses is to be reviled by the people I wrote about," he said. "I've never rejected the world I came from. I've tried to do the opposite, to bring it into the world I'm in. To be rejected by it is horrible. So I hope people will understand that that's actually a much worse privation than any of the physical aspects. I hope we can find a way past it."

Rushdie's wife, American novelist Marianne Wiggins, emerged from hiding earlier this year, saying she could no longer cope with the strain. Rushdie said he has not seen his 11-year-old son Zafar, his child from an earlier marriage, since he went underground. "I think that is an incredible loss to both of us," Rushdie said.

His new book, "Haroun and the Sea of Stories," is a children's fable with many autobiographical touches. Dedicated to Zafar, the book depicts a professional storyteller who is threatened by permanent silence, but is rescued by the heroic efforts of his young son. A new book of Rushdie's essays is due for publication early next year.

Radical Moslem leaders have said Rushdie's expressed contrition will not end the death threat. They insist he must withdraw "The Satanic Verses" from publication and apologize for having written it, steps Rushdie has refused to take.

But the most scathing recent attacks against Rushdie have come from non-Moslems -- relatives of hostages in Lebanon, who contend the Rushdie affair has prolonged their ordeal, as well as right-wing politicians.

In an article ridiculing Rushdie's leftist beliefs, Norman Tebbit, a Conservative member of Parliament, termed Rushdie "an outstanding villain," and said, "His public life has been a record of despicable acts of betrayal of his upbringing, religion, adopted home and nationality." Bragg described the Tebbit article as "disgusting, ignorant, abusive and offensive," and many others have condemned it.