In the 1992 currency reform, 1 new dinar was exchanged for 10 old dinars.
Their exchange rate, the officials said, would be one "Swiss dinar" - the currency used in northern Iraq - for every 150 new dinars.
Today one dollar equals about 13 new dinars, or 130,000 old dinars.
The new currency, in denominations of one, 5 and 10 new dinars, is to be issued first to pensioners.
For an interim period, the old currency will also be used, at the rate of 13 million old dinars to one new dinar.
More importantly, marks can be converted or deposited for the new dinars.
Two attacks were on allied convoys delivering new Iraqi dinars to banks.
The last redenomination of the currency occurred in 1965, when 100 old dinars were replaced by one new dinar.
In 1965, a new dinar was introduced.
Two weeks ago, the new dinars were being sold for a penny, while the prewar bills brought 3 cents.