Tehran's top envoy has closed Iran's London embassy and has flown home, warning that Britain faces the growing wrath of the Moslem world over the Salman Rushdie affair.

Charge d'affaires Mohammad Basti, ordered out by Britain last week, left after Iran's parliament voted to cut ties with London unless it repudiated the writer of "The Satanic Verses" within a week.

Britain countered that future relations depended on Iran's actions, and aboard his plane Tuesday night Basti said Britain had to face the consequences of its refusal to denounce Rushdie's novel.

"It is very unfortunate that your government has taken the lead in making this matter purely political," Basti told BBC. "The more they take this line it will have a disastrous effect for the whole world, for the whole area in the Middle East."

Britain was standing firm on its condemnation of Ayatollah Khomeini's call two weeks ago for the killing of the Indian-born Rushdie.

The novel has outraged Moslems who say it blasphemes against Islam and the Prophet Mohammed. Rushdie, in hiding, has apologized for causing offense and says his book is a surreal parable about good and evil.

Moscow said Tuesday it might be willing to mediate in the affair, which was discussed Monday by Soviet Foreign Minister Eduard Shevardnadze in Tehran.

With Basti's depature, there are no direct links between Britain and Iran, and the Foreign Office said it would welcome Soviet help.

Basti made it clear, however, the death order would stand. "It is not a threat as you suggest. It is a divine order in the holy book of the Moslems."

At least 20 people have been killed in protests against the book by fundamentalists, and some worried booksellers have withdrawn copies.

President Bush denounced attacks linked to the novel after firebombs were tossed at a New York newspaper office and two California bookstores Tuesday.

"This country was founded on the principles of free speech and religious tolerance. I want to make it unequivocally clear the United States will not tolerate any assault on these rights," Bush said.

Many Western countries, including Britain, have recalled diplomats from Iran over the death order. Austria Tuesday joined the list and said it would not send its ambassador back to Tehran in the near future.

An Iranian newspaper urged the government Wednesday to sever ties with West Germany as well.

Tehran's daily Abrar said delivering a similar ultimatum to West Germany would have an impact on other Western nations that have condemned Khomeini for issuing the death decree against Rush-die.

The Abrar said "it would be difficult for Britain to ignore its exports to Iran, which stood at 250 million pounds ($436 million) in 1988. "West Germany, with three times as much exports to Iran, would also not bear the consequences of breaking relations with Iran so easily," the official Islamic Republic News Agency quoted the Abrar as saying.

Authorities said there was no immediate evidence linking the bombings at New York's Riverdale Press and at two Berkeley, Calif., bookstores to Rushdie's novel. But New York Mayor Edward Koch posted a $10,000 reward for information leading to the arrest and conviction of those responsible for bombing the newspaper office.