VIENNA (AP) — In an unusual move, Iran and six world powers on Friday released previously restricted documents about their nuclear deal to enforce their view that Tehran is not circumventing limits on its limit of enriched uranium, which could be used to make nuclear weapons.

Some of the documents are dated Jan.6, 2016, shortly before the pact was implemented. But they were not made public until Friday, when they were posted on the public website of the International Atomic Energy Agency. The IAEA is monitoring the nuclear deal, which Iran reached with Germany and the five permanent U.N. Security Council members — the United States, Russia, China, France and Britain.

The agreement stipulates that Iran can possess only low-enriched uranium, which is not suitable for weapons, and it is limited to possessing no more than 300 kilograms (660 pounds) at any time. That is far less than would be needed to make a nuclear weapon even if it were further enriched to weapons-grade levels used for the core of nuclear warheads.

When the nuclear deal was agreed on, Iran had more than 100 kilograms of liquid or solid waste containing low-enriched uranium as part of its enrichment activities. Some of the material remains and the documents posted Friday declare the low-enriched uranium it contains as "unrecoverable" and thereby not part of the 300-kilogram limit.

A letter on behalf of the European Union's foreign policy chief, Federica Mogherini, authorizing publication of the documents was also posted on the IAEA website. It did not specify why they were made public nearly a year after they were agreed on by the nations negotiating the deal.

But it comes at a time that the incoming U.S. administration has served notice it might seek to pull out of the agreement. Two officials from one of the five permanent Security Council member nations at the table with Iran suggested it was meant to show unity on the issue among criticism from experts that U.S. lawmakers critical of the deal have seized on as an example of allowing Iran to undercut the pact.

Publication of the document comes shortly after the IAEA warned Iran to curb its production of low-enriched uranium or face the possibility of exceeding its allotted limit. The two officials said, however, that the two issues were not related, and Iran for now remained within its obligations.

They agreed to discuss the matter only if they were not quoted by name because they are not authorized to talk about the confidential issue.