DUBAI (Reuters) -Iran has told mediators Qatar and Oman that it is not open to negotiating a ceasefire while it is under Israeli attack, an official briefed on the communications told Reuters on Sunday, as the two foes launched fresh attacks and raised fears of a wider conflict.

"The Iranians informed Qatari and Omani mediators that they will only pursue serious negotiations once Iran has completed its response to the Israeli pre-emptive strikes," said the official, who spoke on the condition of anonymity due to the sensitivity of the conflict.

Iran made "clear that it will not negotiate while under attack," the official said.

Israel launched a surprise attack on Iran on Friday morning that wiped out the top echelon of Iran's military command and damaged its nuclear sites, and says the campaign will continue to escalate in coming days.

Iran has vowed to "open the gates of hell" in retaliation in what has emerged as the biggest ever confrontation between the longstanding enemies.

The official told Reuters media reports that Iran appealed to Oman and Qatar to engage the U.S. to broker a ceasefire and renew nuclear talks were inaccurate.

Iran's foreign ministry did not respond to Reuters request for comment, nor did Qatar's foreign ministry or Oman's ministry of information.

Oman has in recent months mediated nuclear talks between the United States and Iran, though the most recent round was canceled a day after Israel launched a sweeping air offensive against Iran.

Qatar has also played a role facilitating talks between the two foes in the past, most recently mediating a prisoner swap agreement in 2023.

Oman and Qatar have good relations with both Iran and the U.S. and they also have communicated directly with Israel.

(Reporting by Andrew Mills; additional reporting by Parisa Hafezi; Editing by Chizu Nomiyama)