The world's major powers are discussing possible new sanctions against Iran including a travel ban, an expanded list of people and companies subject to an asset freeze, an arms embargo and trade restrictions — but differences remain, council diplomats said.

Ambassadors from the five permanent council nations — the U.S., Russia, China, Britain and France — and Germany met Tuesday for a second day to try to reach agreement on the measures to include in a new U.N. resolution to increase pressure on Iran which refuses to suspend uranium enrichment.

Foreign ministry political directors from the six countries scheduled a conference call Wednesday to take up the sanctions issue again in an attempt to resolve the differences, Security Council diplomats said, speaking on condition of anonymity because the discussions are private.

China's U.N. Ambassador Wang Guangya, whose country has close ties to Iran, said Tuesday there were different views on curbing loan guarantees for companies doing business in Iran.

Acting U.S. Ambassador Alejandro Wollf said the United States wants a ban on the import and export of arms, but he said the scope of an embargo was one of the issues being discussed.

Foreign ministry political directors from the six countries held three rounds of talks over the past week on strengthening sanctions against Iran following a report earlier this month by the U.N.'s International Atomic Energy Agency that Iran was expanding enrichment instead of suspending it. They sent the issue to their Security Council ambassadors this week to start drafting a new resolution.

Iran's refusal to freeze all its enrichment-related activities prompted the Security Council on Dec. 23 to impose sanctions. 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 and that is what members are now considering.

Iran insists its enrichment program is peaceful and aimed at producing nuclear energy, but the U.S., European countries and the IAEA are concerned that Tehran's real aim is to produce nuclear weapons.

During negotiations on the December sanctions resolution, the U.S. administration pushed for tougher penalties but Russia and China, which both have strong commercial ties to Tehran, and Qatar, across the Gulf from Iran, balked.

To get their votes, the Dec. 23 resolution dropped a ban on international travel by Iranian officials involved in nuclear and missile development and specified exactly which items and technologies were banned.

After Tuesday afternoon's meeting, Britain's U.N. Ambassador Emyr Jones Parry said "we don't have a text as such, but we've been looking at elements of what actually go into the resolution and we're making progress."

He said the new resolution "would be an incremental ratcheting up of the measures," and he added, "I think we're moving incrementally on the subject."

South Africa's U.N. Ambassador Dumisani Kumalo, the current Security Council president, said Jones Parry told the council earlier Tuesday that the six countries are looking at four areas for new sanctions.

The possibilities are adding names of people and entities to the list and imposing a travel ban, restricting arms exports and imposing trade restrictions, he said.

The U.S., Britain and France would almost certainly favor tough new sanctions, but they know they will have to settle for less to ensure that Russia and China will not use their veto power to block a new resolution.

Kumalo said the six countries emphasized that they want "to try and align the position among themselves on some issues" before distributing a text to the 10 non-permanent council members who serve two-year terms.

"I'll be very disappointed if we don't get it by the middle of the week," he said.