The major powers moved closer to agreement Monday night on a modest package of new sanctions against Iran likely to include an embargo on Iranian arms exports and an asset freeze on more individuals and companies associated with Tehran's nuclear and missile programs.

A new sanctions resolution is also likely to include a ban on government loans to Iran, council diplomats said. But a travel ban is out, and there will likely be no ban on arms imports or on export credit guarantees for companies doing business in Iran.

Ambassadors from the five veto-wielding permanent Security Council nations — the United States, Russia, China, Britain and France — and Germany emerged from a closed-door meeting far more optimistic than ever before but also cautious because of potential problems with every proposal in the package.

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"This is the best meeting we have had since the beginning of these negotiations," said France's U.N. Ambassador Jean-Marc de La Sabliere. "We are now very close, and we have made today (much) progress."

Acting U.S. Ambassador Alejandro Wolff said ambassadors would report to their capitals on the possible elements for a new resolution and wait to see if they're approved or if changes are needed.

"There are still some concerns, and some delegations have not given full agreement. But we have, I think, made overall good progress," he said. "It's a package approach, and so there are things that we're very pleased about, and things that we're less pleased about — and likewise for probably every delegation involved."

The Security Council is meeting on Somalia on Tuesday and the permanent members are expected to report afterwards on their progress in putting together an Iran resolution.

"If everything goes well, our hope would be to get it done by the end of the week — a vote," Wolff said.

But he cautioned that there is still no draft resolution and it must be discussed with the 10 nonpermanent council members.

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 warned it would adopt further nonmilitary sanctions if Iran refused to comply.

As a result of Iran's expansion of its enrichment program in defiance of the council, the three European countries that have led negotiations trying to rein in Iran's nuclear program and the other permanent council nations have been considering possible new sanctions. They include a travel ban, an arms embargo, trade restrictions, and an expanded list of people and companies subject to an asset freeze.

The United States and the Europeans favored all the measures but Russia and China, which have close commercial ties with Iran, are reluctant to impose tough new sanctions.

China's U.N. Ambassador Wang Guangya said the six countries agreed to impose an embargo on arms exports from Iran — but not on imports. The six are still debating whether to ask the 191 other U.N. members states to "exercise vigilance or restraint" in selling seven categories of heavy weapons to Iran.

There also appears to be agreement on expanding the list of individuals and entities subject to an asset freeze. Li Junhua, a senior diplomat in China's U.N. mission, said a much bigger list of individuals and entities was now being studied by the six governments in their capitals.

Wolff said "one of the trickiest issues that we're still discussing" is a proposal to freeze the assets of companies controlled by Iran's Revolutionary Guards, an elite corps that oversees vital Iranian interests, including oil and natural gas installations and the nation's missile arsenal.

Russia has raised concerns that mentioning the Revolutionary Guards would amount to censuring the entire institution.

Russia's U.N. Ambassador Vitaly Churkin cautioned about possible problems saying "the devil is in the details."

To win unanimous council approval of the December resolution, a mandatory travel ban was dropped.

The resolution that was adopted calls on all states "to exercise vigilance" regarding the entry or transit through their territory of the Iranians on the U.N. list. It asks U.N. member states to notify the Security Council committee monitoring sanctions when those Iranians show up in their country.

Li said the new resolution would generally follow that language, calling on countries to "exercise vigilance and restraint."

In the financial area, China has resisted proposed cutbacks on loan guarantees for companies doing business in Iran, a measure strongly supported by the United States.

Wang indicated that the only financial or trade measure likely to be approved is the ban on government loans to Iran.

As in the December resolution, the diplomats said the new resolution is expected to ask U.N. nuclear chief Mohamed ElBaradei, who heads the International Atomic Energy Agency, to report to the council on Iran's compliance in 60 days.

"This is an incremental effort to try to get Iran back to negotiations by suspending its enrichment activities and in addition demonstrating that violating U.N. Security Council resolutions and remaining in non-compliance comes with a price," Wolff said.

Council diplomats said they have not yet received a formal request following up on Sunday's surprise announcement by the Iranian government spokesman that President Mahmoud Ahmadinejad wants to put Tehran's case for a nuclear program before the Security Council.

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

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