Iran's Foreign Ministry says Tehran will seek a world free of nuclear weapons when it holds an international nuclear summit next Saturday.
Foreign Ministry spokesman, Ramin Mehman-Parast, said Wednesday he also doubts that countries participating in a nuclear summit in Washington truly intend to reduce their stockpiles of nuclear weapons.
The United States will host leaders from 47 nations during a two-day nuclear summit scheduled to begin on Monday.
The following Saturday, Iran says it will host representatives from 60 countries during a two-day nuclear disarmament conference.
Friday, Iranian President Mahmoud Ahmadinejad unveiled a new generation of domestically-built centrifuges that can enrich uranium six times faster than its older ones.
In Washington, State Department spokesman P.J. Crowley said the United States has to conclude that Iran has "nefarious intentions" in its nuclear activities, because a peaceful nuclear program would have no need for faster centrifuges.
International leaders believe Iran is trying to secretly develop nuclear weapons. Tehran says its nuclear program is for peaceful purposes only.
This week, six world powers began negotiations on a possible new round of U.N. Security Council sanctions against Tehran for its nuclear activities. Those nations include Germany and the five permanent council members - the United States, Britain, France, Russia and China.
Iran announced its nuclear disarmament summit on April 4.