Senior officials from the United States, Japan and four other South Korean allies have discussed Seoul's recently disclosed nuclear activities on the sidelines of the IAEA Board of Governors meeting in Vienna.

At Wednesday's informal talks organized by Seoul's Ambassador to Austria, Cho Chang-bum, participants exchanged views on recent revelations that South Korean scientists had carried out secret uranium and plutonium experiments in the 1980s and in 2000.

Ambassador Cho made clear that the experiments were carried out independently by a group of scientists for research purposes, expressing hope that there would be no misunderstanding on Seoul's commitment to non-nuclear proliferation.

Participants of the informal meeting reportedly expressed concerns over the issue, but were quick to agree on the desirability of a prompt resolution of the controversy.

The IAEA board is scheduled to address South Korea's nuclear activities on Friday or Saturday after first concluding discussions on Iran's suspected nuclear weapons programs on Thursday.