"When oil prices change by $10 to $15 by official comments (about the market), oil prices will be pushed to unpredictable highs if some take an unwise decision to attack Iran," it quoted Oil Minister Gholamhossein Nozari as saying.

The Islamic Republic insists its nuclear programme is peaceful and aimed at generating electricity. But the West and Israel fear Iran is seeking to build atomic bombs. Israel is believed to be the only Middle East state with nuclear arms.

Speculation about a possible attack on Iran because of its disputed nuclear ambitions has risen since a report this month said Israel had practised such a strike, prompting increasingly tough talk of retaliation, if pushed, from Tehran.

Iran's elite Revolutionary Guards warned last week Tehran would impose controls on shipping in the vital Gulf oil route if Iran was attacked.

Agencies