The government assured novelist Salman Rushdie of its unwavering support Saturday, and Iran suggested London could defuse the crisis over Rushdie's new novel by banning the book and prosecuting the writer.

The Indian-born author questioned government support for him Friday after Prime Minister Margaret Thatcher and Foreign Secretary Sir Geoffrey Howe said Rushdie's "The Satanic Verses" has offended some Britons as well as Moslems.Tehran Radio welcomed their statements Saturday but demanded Britain take "concrete action."

"The British government, by accepting that the book is insulting, cannot object to the death sentence on the writer, which has been issued in line with Sharia (Islamic law)," it said.

Iran's parliament speaker, Hashemi Rafsanjani, considered leader of the pragmatist camp within the Iranian hierarchy, said the rift over the book "seems difficult to heal."

"Even if the apostate Rushdie is executed, if Britain apologizes or if the book is withdrawn, the rift remains part of a global arrogance plot," the radio quoted Rafsanjani as saying. He offered no suggestions as to how the controversy could be resolved.

Britain repeatedly has demanded Iran's spiritual leader, Ayatollah Ruhollah Khomeini, rescind his Feb. 14 death sentence on Rushdie for writing the novel, which some say insults Islam.

The Foreign Office reiterated Saturday that Britain will not discuss the Rushdie affair with Iran until the death threat is withdrawn.

Rushdie, 41, who was born into a Moslem family in India, is in hiding.