Vienna: In an unusual move, Iran and six world powers have released previously restricted documents about their nuclear deal to enforce their view that Tehran is not in a position to try to make nuclear weapons.

Some of the documents are dated January 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 UN 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 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 on 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, authorising publication of the documents was also posted on the IAEA website.

It comes at a time that the incoming US administration has served notice it might seek to pull out of the agreement.

This week, US President-elect Donald Trump said on Twitter that the US should "strengthen and expand" its own nuclear capabilities.

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.

This follows criticism from experts that US Congress members critical of the deal have seized on it 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.

AP