Susan Rice said the president wants to focus on the issues he raised in a speech April 5 in the Czech Republic, in which he pledged to eventually eliminate nuclear weapons.

In the Prague speech, Obama called for the slashing of U.S. and Russian nuclear arsenals, adoption of the treaty banning all nuclear tests, and negotiations on a new treaty that "verifiably" ends the production of materials used to make atomic weapons.

"It's an opportunity for the council, which obviously has a deep stake in nuclear nonproliferation and nuclear disarmament, to continue its thinking and to concert its action," Rice told reporters.

She said invitations have been sent to leaders of the 14 other council nations _ including nuclear powers Russia, China, Britain and France _ to attend the special council meeting on Sept. 24, the second day of the U.N. General Assembly's annual ministerial meeting. Obama will address the assembly's opening meeting on Sept. 23 and will chair the nonproliferation session because the U.S. holds the rotating presidency of the Security Council in September.

Rice refused twice to say whether the council meeting would produce a resolution or statement. She said in Tuesday's statement that the U.S. would be working with council members in the coming weeks to prepare for the meeting _ and a U.S. official added Wednesday that the work will including efforts "to make it a productive session."

Rice was asked why Tuesday's announcement of the special session said it would focus on broad issues "and not on any specific countries."

"There are many, many issues out there that are important and relevant that go beyond individual countries," she replied.

Rice said the United States wants to secure loose nuclear material within four years, start a follow-on agreement to reduce U.S. and Russian nuclear arsenals, ratify the nuclear test ban treaty, and negotiate a treaty to end production of bomb-making fissile materials.

"We are dealing with the individual countries every day in the Security Council," she said.

She cited recent new sanctions against North Korea for defying the council and conducting a second nuclear test and the continuing review of Iran which is also under U.N. sanctions for its refusal to susend uranium enrichment, a key ingredient of nuclear weapons.

"So this is an opportunity that we very much welcome _ to bring the Security Council further into the discussion of the sorts of topics that president Obama raised in his speech in Prague," Rice said.

The council meeting will take place ahead of next year's major conference to review the Nuclear Nonproliferation Treaty.

The treaty requires signatory nations not to pursue nuclear weapons in exchange for a commitment by the five nuclear powers to move toward nuclear disarmament. The nonweapons states are guaranteed access to peaceful nuclear technology to produce nuclear power.

Unlike the last review conference in 2005 which was a failure, delegates preparing for the 2010 meeting already agreed on an agenda in May, and some said the change in Obama's tone and emphasis in Prague was a key factor.

"Obviously the NPT review conference is an important milestone and we're very much committed to working to make it a success," Rice said, "and to the extent that this session of the Security Council can lend positive impetus to that, we would find that very valuable."