TEHRAN: Iran's underground uranium enrichment facility will go on stream soon, a senior official was quoted by Iranian media on Sunday as saying, a move likely to increase tension between the Islamic state and the West over Tehran's nuclear ambitions.

“The Fordow nuclear enrichment plant will be operational in the near future ... 20 per cent, 3.5 per cent and four per cent enriched uranium can be produced at this site,” said the head of Iran's Atomic Energy Organisation Fereydoun Abbasi Davani, the Kayhan daily reported.