Israel on June 11 denied spying on the nuclear negotiations between Iran, the United States, and other world powers.
"There is no basis to all the international reports on Israel's involvement in the affair," Israeli Deputy Foreign Minister Tzipi Hotovely told Israeli army radio.
While Swiss and Austrian authorities are investigating evidence of cyberspying on the delegations attending the talks and the hotels where they stayed, no one has directly accused Israel of perpetrating the attacks.
Cybersecurity firms say, however, that the hacking techniques used resemble viruses used by Israel in the past.
An Iranian envoy told Iran state TV that he was "not surprised" about the spying, but said Iran's negotiators were careful to protect their secrets.
"These talks have enemies, especially the Zionist regime, which doesn't want the negotiations to succeed," he said.
The United States also was confident that it hasn't spilled any secrets.
"We've taken steps throughout the negotiations to ensure that confidential details and discussions remain behind closed doors," said State Department spokesman Jeff Rathke.