An exiled Iranian opposition group said on Thursday a delegation of North Korean nuclear and missile experts visited a military site near Tehran in April amid talks between world powers and Iran over its nuclear program.

The dissident National Council of Resistance of Iran (NCRI) exposed Iran¡¯s uranium enrichment plant at Natanz and a heavy water facility at Arak in 2002. Analysts say it has a mixed record and a clear political agenda.

Iran says allegations that it is trying to develop a nuclear weapons capability are baseless and forged by its enemies.