World and Nation

Obama Pushes To Update Global Rules on Nuclear Arms

President Barack Obama moved on Thursday to tighten the noose around Iran, North Korea and other nations that have exploited gaping loopholes in the patchwork of global nuclear regulations.

Obama pushed through a new U.N. Security Council resolution that would, if enforced, make it more difficult to turn peaceful nuclear programs into weapons projects.

But as Obama sat in New York as chairman of the Security Council — a first for a U.S. president, meant to symbolize his commitment to rebuild the council’s tattered authority — he received a taste of the opposition he is likely to face on some of his nuclear initiatives.

Some developing and nonnuclear nations bridled at the idea of Security Council mandates and talked of a “nuclear free zone” in the Middle East. That is widely recognized as a code phrase for requiring Israel to give up its unacknowledged nuclear arsenal.

The Security Council meeting was the last major business at the United Nations before Obama arrived here for an economic summit meeting of the Group of 20. It capped three days of intensive diplomacy leading up to the first direct negotiations with Iran in decades that will involve a representative of the United States, scheduled for next Thursday.

But Obama used the meeting to broaden the issue, hoping to stop an incipient arms race in the region and rewrite outdated treaties, starting with a review of the 1972 Nuclear Nonproliferation Treaty next year.

“This is not about singling out an individual nation,” Obama said. “International law is not an empty promise, and treaties must be enforced.”

Yet Iran was the subtext of every conversation.

At the end of Obama’s three days of public and private arm-twisting, it was still unclear how many other leaders were committed to what the White House once called “crippling sanctions” against Iran if it continues making nuclear fuel and refuses to respond to questions about evidence it worked on the design of a nuclear weapon.

Russia’s president, Dmitri A. Medvedev, sounded more open to supporting sanctions at a meeting with Obama in New York. But that position seemed at odds with statements last week by Prime Minister Vladimir V. Putin, who regularly angered President George W. Bush for his refusal to sign on to sanctions that might seize the attention of Iran’s ruling elite.

Medvedev spoke generally, and did not embrace any specific ideas for sanctions, including discussion of cutting off Iran’s access to refined gasoline imports.

More mysterious is whether Obama convinced China’s president, Hu Jintao.

“We’ve been trying to convince him that if this gets out of control, China’s own interests — especially in oil — will be hurt, so they better get involved,” one senior aide to Obama said.

But Hu talked instead at Thursday’s meetings of arms cuts among the major powers, noting that China possesses only “the minimum number of nuclear weapons” needed for its own security.