Israeli officials believe Iran is weeks away from enriching uranium to a level sufficient for building a nuclear weapon.

The amount of uranium Iran has enriched to 20-percent purity is critical, because reaching a certain threshold – known as the significant quantity (SQ) – means the stockpile can rapidly be enriched to the 90-percent purity needed for a nuclear weapon. Iran possessing a stockpile of 220 kilograms of uranium enriched to 20 percent would mean it had reached the significant quantity. 

According to intelligence shared by a number of countries, including Israel, the amount of uranium Iran has enriched to 20-percent purity and to 60-percent purity make Tehran just a number of weeks away from having enough enriched uranium to further purify it to 90 percent.

Israeli officials are concerned by the numbers, and have asked that an end to further enrichment be among the demands made to Iran during renewed talks over its nuclear program.

On Monday, Prime Minister Naftali Bennett called on world powers not to “give in to Iran’s nuclear blackmail.”

In a video statement that was delivered to representatives of nations opening negotiations with Iran, Bennett said that Tehran seeks “to end sanctions in exchange for almost nothing” and keep its nuclear program intact while receiving hundreds of billions of dollars once sanctions are lifted.

There has been pessimism in Israel in recent days over the resumption of the Vienna talks. According to assessments, the round of talks will not lead to real progress in the immediate term between the two sides. Officials had the sense that Iran is not interested in a return to the nuclear agreement and instead would drag out the talks, enabling it to advance its nuclear program under the radar.

Israeli sources expect Iran to make uncompromising demands in Vienna while the Americans, who at Iran’s insistence will not have their representatives in the room, will demand that Tehran return to full compliance with the nuclear agreement signed in 2015. The expectation is that the diplomatic drama between Iran and the United States will only begin after this round of talks.