U.N. ambassadors from six world powers agreed in principle Wednesday on a proposed new package of sanctions against Iran and were expected to introduce a resolution to the Security Council on Thursday if their governments approve it, the U.S. ambassador said.

The package still needs to be considered by the 10 non-permanent members of the U.N. Security Council that haven't been part of the negotiations. However, an agreement by the five veto-wielding permanent members of the council and Germany would be a strong signal that they want to send a united message to Iran to suspend uranium enrichment.

"We have an agreement in principle based on some additional changes that were introduced and presented today by some delegations," acting U.S. Ambassador Alejandro Wolff said.

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He said the new elements needed to be approved by government officials in each of the five countries that hold permanent council seats — the U.S., Russia, China, France and Britain. But he called it a "package approach" that "would be essentially the way forward in a resolution."

Russia's U.N. Ambassador Vitaly Churkin said "by and large it has been agreed."

He said some of the council members still want to consult with their governments on the details. "I assume as they double check, they will get a positive response from the capitals, and they expect that this is going to be the case, too," he said.

Iran insists its enrichment program is peaceful and aimed solely at producing nuclear energy, but the U.S., European nations and the U.N. nuclear watchdog are concerned that Iran's goal is to produce nuclear weapons.

In December, the Security Council voted unanimously to impose limited sanctions against Iran for its refusal to freeze uranium enrichment. It ordered all countries to stop supplying Iran with materials and technology that could contribute to its nuclear and missile programs and to freeze assets of 10 key Iranian companies and 12 individuals related to those programs.

The council said it would consider further nonmilitary sanctions if Iran refused to suspend enrichment. Iran's response was to accelerate its enrichment program.

The modest package of new measures agreed to by the ambassadors of the six countries includes an embargo on Iranian arms exports and an asset freeze on more individuals and companies associated with Tehran's nuclear and missile programs, council diplomats said.

The new resolution would also call on all U.N. member states to exercise "vigilance and restraint" on arms imports and on the entry or transit through their territory of Iranians subject to the asset freeze, a council diplomat said, speaking on condition of anonymity because the text has not been circulated.

It would also call on governments to make no new commitments "of grants, financial assistance, or concesssional loans to the government of Iran," the diplomat said.

The United States and the Europeans would certainly favor tougher sanctions, but knew they had to settle for less to ensure that Russia and China, which have close commercial ties with Iran, will not use their veto power to block a resolution.

China's U.N. Ambassador Wang Guangya said he wasn't happy with the list of additional individuals and entities that would be subject to sanctions, but he added: "I think one has to reach agreement, so there has to be a package."

Earlier Wednesday, Israel's Foreign Minister Tzipi Livni and Defense Minister Amir Peretz met with U.N. Secretary-General Ban Ki-moon to discuss Iran's nuclear program.

Afterward, Livni urged the Security Council to strengthen its sanctions on Iran. She said Iran's government, which speaks publicly of wiping Israel off the map and denies the Holocaust, is a threat not only by Israel but to Iran's Arab Muslim neighbors.

She said it is "clear that their goal is to pursue a nuclear weapon. Time is of the essence because while we are talking, they are working ... to master the technology and to achieve this goal. So we have to stop it."

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