Media in Iran on Sunday speculated that a US plot may have been behind Friday's stabbing of novelist Salman Rushdie at a literary event in the United States.

Two days after the writer was attacked on stage in upstate New York, coverage was muted in the Islamic republic, whose founder the late Ayatollah Ruhollah Khomeini issued a fatwa, or religious decree, calling for Rushdie to be killed.

Most newspapers did not mention the attack, and two ultra-conservative dailies that did saw a change in tone.

"The Satanic Verses" and "Midnight's Children" author had lived in hiding for years after Khomeini ordered his killing.

Rushdie is in hospital in the United States where he was reported by his agent on Saturday as being able to talk again after undergoing emergency surgery.

Following Friday's stabbing, some Iranian media reports had hailed the attack.

"The Satanic Verses" enraged some Muslims who said it was blasphemous for its portrayal of Islam and the Prophet Mohammed.

On Sunday, the ultra-conservative daily Javan suggested that the attack may have been a plot hatched by the Americans.

"Maybe a young Muslim, who was not even born when Salman Rushdie wrote his satanic book, wanted revenge on him," it said.

Hadi Matar, the 24-year-old man accused of stabbing Rushdie, pleaded not guilty to attempted murder charges on Saturday.

"Another scenario is that the United States probably wants to spread Islamophobia around the world," Javan wrote.

Tha daily Kayhan, which on Saturday hailed the attacker as "courageous and duty-conscious", went on to suggest that attacks on other figures could be possible in the future.

"The attack on Salman Rushdie highlighted the weakness of US intelligence and demonstrated that even strict security measures cannot prevent attacks," Kayhan wrote.

It "proves that exacting revenge on criminals on American soil is not difficult".

"Now (former US president Donald) Trump and (former secretary of state Mike) Pompeo will feel more threatened," the paper added.

In January, Iran's President Ebrahim Raisi vowed revenge against Trump unless he faces trial over the killing of revered commander Qasem Soleimani, as Tehran marked two years since his death.

General Soleimani and his Iraqi lieutenant were assassinated in a US drone strike at Baghdad airport in January 2020.

Kayhan called the attack on Rushdie "a warning to those behind Soleimani's assassination that they must know revenge is close, even if they are well-protected".

Iran's authorities have kept total silence over the attempt to kill the British-American author who was stabbed about 10 times in what the US authorities called a premeditated assault.

Thierry Coville, an expert on Iran at the French Institute for International and Strategic Affairs, or IRIS, said he does not think the authorities were involved.

"I don't see the hand of the Iranian state in this attack, but what is certain is that it will increase mistrust of Iran in the United States," he told AFP.