Iran said on Monday U.S. cyber attacks on its military had been a failure, while also hinting that it could be willing to discuss new concessions with Washington if the United States were to lift sanctions and offer new incentives.

The longtime foes have come the closest in years to a direct military confrontation.

After Iran shot down a U.S. drone last week, U.S. President Donald Trump said he had called off a retaliatory strike while bombers were in the air, deciding that too many people would die.

U.S. media have reported that the United States launched cyber attacks even as Trump called off the air strike.

The Washington Post said on Saturday that the cyber strikes, which had been planned previously, had disabled Iranian rocket launch systems. U.S. officials have declined to comment.

“They try hard, but have not carried out a successful attack,” Mohammad Javad Azari Jahromi, Iran’s minister for information and communications technology, said on Twitter.

“Media asked if the claimed cyber attacks against Iran are true,” he said. “Last year we neutralized 33 million attacks with the (national) firewall.”

Allies of the United States have been calling for steps to defuse the crisis, saying they fear a small mistake on either side could trigger war.

“We are very concerned. We don’t think either side wants a war, but we are very concerned that we could get into an accidental war and we are doing everything we can to ratchet things down,” British Foreign Secretary Jeremy Hunt said.

*This story was edited by Ahram Online