The Islamic Republic of Iran has said that there will be a “proportiate response” should a Western-back resolution critical of its nuclear program pass at the International Atomic Energy Agency Board of Governors meeting in Vienna this week.

If the parties “ignore Iran’s goodwill and interactive approach and put non-constructive measures on the agenda in the Board of Governors meeting through the issuance of a resolution, Iran will respond in a proportionate and appropriate manner,” Iranian Foreign Minister Abbas Araghchi said in a phone conversation with IAEA Director Rafael Grossi on Wednesday, AFP reported.

Diplomatic sources told AFP that Britain, France and Germany had submitted the resolution just before midnight on Tuesday.

The IAEA’s quarterly November board meeting of its 35 member nations convenes on Wednesday and diplomats said that Paris, Berlin and London were planning to present the resolution for a vote probably on Thursday, despite Araghchi’s warning.

Speaking with his French counterpart Jean-Noel Barrot, Araghchi “strongly condemned the decision of the three countries of Germany, France and the United Kingdom” for officially asking the IAEA to censure Iran over its lack of cooperation regarding its nuclear activities, saying that it “will only complicate the matter further,” Iran’s Foreign Ministry said on Wednesday.

Araghchi also told Barrot over the phone that the move was “in clear contradiction to the positive atmosphere created in the interactions between Iran and the agency.”

Tehran offered not to increase its uranium stock beyond the current amount in a bid to prevent the resolution from moving ahead, Reuters reported on Tuesday, citing one of two quarterly IAEA reports seen by the news agency.

During Grossi’s trip to Iran last week, “The possibility of Iran not further expanding its stockpile of uranium enriched up to 60% U-235 was discussed,” the report stated, adding that the IAEA had verified that Iran had “begun implementation of preparatory measures.”

A senior diplomat told Reuters that the pace of enrichment had slowed, which is a necessary step before stopping.

“Stopping enriching to 60%, great, they shouldn’t be doing that in the first place as we all know there’s no credible civilian use for the 60%,” one Western diplomat told Reuters, adding: “It’s something they could switch back on again easily.”

However, Iran has continued to expand its stockpile of uranium enriched to near-weapons-grade levels, the Associated Press reported on Tuesday, citing a confidential IAEA report.

As of Oct. 26, Tehran had 182.3 kilograms (401.9 pounds) of uranium enriched up to 60% U-235, an increase of 17.6 kilograms (38.8 pounds) since its last report in August.

This level of enrichment is just a technical step from 90% enrichment, considered weapons grade. According to the IAEA, it is possible to create an atomic bomb with roughly 42 kilograms (92.5 pounds) of uranium enriched to 60% if the material is further enriched to 90%.