Iran is constructing a production hall for advanced uranium enrichment centrifuges as a response to the recent fire meant to “sabotage” the country’s development of the machines, according to a statement issued by the country’s nuclear chief.

“Due to the sabotage, it was decided to build a more modern, larger and more comprehensive hall in all dimensions in the heart of the mountain near Natanz. Of course, the work has begun,” said Ali Akbar Salehi, Iranian diplomat and head of the Atomic Energy Organization of Iran (AEOI), according to Reuters, which cited state TV.

The “sabotage” Salehi spoke of refers to the July 2 fire and subsequent explosion that took place at the Natanz nuclear site, the country’s largest uranium enrichment facility. Iranian officials initially suspected a gas leak was responsible for the incident, which did not result in radioactive leaks or other significant damage, but a more thorough investigation has since been launched by Tehran.

This comes amid ongoing tensions between the US, Iran, and the United Nations Security Council’s (UNSC) rejection of a US-led draft resolution to extend the weapons embargo initiated under the 2015 Joint Comprehensive Plan of Action (JCPOA).

US Secretary of State Mike Pompeo declared prior to the UNSC vote last month that the Trump administration will do “everything within our diplomatic toolset to ensure that the arms embargo doesn’t expire” on October 18.

“We have been unambiguous about the fact we have no intention of allowing this arms embargo to expire. None whatsoever,” Pompeo underscored.