Iran has given the U.N. nuclear agency documents linked to the agency's probe of allegations that Tehran tried to develop atomic arms.

The U.N.'s International Atomic Energy Agency says Iran also provided an explanation of what the documents mean.

The agency gave no details. But any Iranian explanation is unlikely to veer from previous denials of work on such weapons.

Announced Saturday by the IAEA, the development meets a key deadline Iran has committed to as part of its overarching deal with six world powers promising Tehran sanctions relief in exchange for nuclear concessions.

The July 14 deal's main focus is curbing Iran's present nuclear program that could be used to make weapons. But a subsidiary element obligates Tehran to cooperate with the IAEA in its probe of the allegations.