Iran leader calls USD a worthless piece of paper

Iranian President Mahmoud Ahmadinejad has suggested an end to the trading of oil in US dollars, calling the currency "a worthless piece of paper".

The call came at the end of a rare Opec summit, and was opposed by US ally Saudi Arabia.

The Iranian president had wanted to include the attack on the dollar in the summit's closing statement.

The communique made little mention of the dollar, however, focusing instead on energy security and the environment.

Speaking after the end of the summit, Mr Ahmadinejad said all leaders at the meeting were unhappy with recent falls in the value of the dollar.

The dollar has weakened considerably against the euro and other currencies in the past 12 months.

Its decline has affected the revenues of Opec members because most of them price and sell their oil exports in the US currency.

Mr Ahmadinejad said that all Opec countries had showed interest in converting their cash reserves into other currencies.

"They [the US] get our oil and give us a worthless piece of paper," he told reporters.

Iran's oil minister said that this would allow the formation of a committee to study the dollar's affect on oil prices and investigate the possibility of alternative trading currencies.