The spokesman of Iran's Atomic Energy Organization says Tehran will go ahead with the "third step" in reducing its commitments under the 2015 nuclear deal if the European parties to the agreement fail to fulfil their obligations within the next month.

Behrouz Kamalvandi told reporters on Monday August 5 that Tehran will watch developments closely during this month.

He added: "So far we have not seen any positive developments that would eliminate the need for Iran to reduce its commitments."

In two steps following a threat made by Iran's President Hassan Rouhani on the anniversary of the U.S. withdrawal from the nuclear accord, Iran exceeded the 3.67 percent Uranium enrichment level and the 300-kilogram stockpile limit on its enriched Uranium since May.

Iran wants Europe to facilitate Tehran's oil exports and repatriation of its oil money in spite of U.S. sanctions. Europe has promised to help with a special financial mechanism, which Iran says is no good unless Iran can sell oil in the international markets.

Kamalvandi said on Monday that "Iran's Uranium stockpile is on the rise and its heavy water equipment are working with full capacity," adding that Iran has exceeded the 130 ton limit for its heavy water reserves.

He threatened that if Europe does not take a serious measure to help Iran, Tehran's commitments will be gradually dropped so that eventually nothing will remain of the nuclear deal.

Europeans have said previously that they do not accept any ultimatum by Iran.