Iran blames its regional arch-foe Israel for Sunday’s incident at the Natanz nuclear site and will take its revenge, state TV quoted Foreign Minister Mohammad Javad Zarif as saying on Monday.

Iranian authorities described the incident a day earlier as an act of “nuclear terrorism” and said Tehran reserves the right to take action against the perpetrators.

“The Zionists want to take revenge because of our progress in the way to lift sanctions … they have publicly said that they will not allow this. But we will take our revenge from the Zionists,” Zarif was quoted as saying.

Multiple Israeli media outlets have quoted unnamed intelligence sources as saying that the country’s Mossad spy service carried out a successful sabotage operation at the Natanz site, potentially setting back enrichment work there by months. Israel has not formally commented on the incident.

The Natanz uranium-enrichment site, much of which is underground, is one of several Iranian facilities monitored by inspectors of the International Atomic Energy Agency (IAEA), the U.N. nuclear watchdog.

Reuters