Iraq said on Friday it was resuming exploration of its immense oil reserves after a break of nearly 20 years due to crippling UN sanctions, saying it hopes to double its proven deposits of crude.

"Today the Iraqi oil ministry celebrates a return to work by Iraqi oil exploration teams after 20 years of interruption," ministry spokesman Assim Jihad told AFP.

Oil Minister Hussein Hussein al-Shahristani was to attend a ceremony to mark the event at the Al-Garraf field near Nasiriyah, 350 kilometres (220 miles) south of Baghdad, Jihad said.

He said the ministry would deploy three exploration teams trained abroad in the latest techniques.

OPEC member Iraq hopes the squads will uncover deposits that will enable it to double its proven oil reserves, currently standing at 115 billion barrels of crude.

With the dollar strengthening on Friday, crude prices in London slumped below 116 dollars a barrel amid concerns about slower energy demand and as Iraq resumed exploration.