UNITED NATIONS — Top officials in the foreign offices of six world powers met in Washington yesterday to coordinate their policies on Iran — even as their U.N. ambassadors tried to rally members of the Security Council around a new resolution to sanction Iran because of its nuclear activity.

Speaking on condition of anonymity, a Western diplomat at the United Nations said it was “highly unusual” for the foreign office political directors of France, Britain, Russia, China, and Germany to fly to Washington to discuss policies on Iran just as New York-based diplomats moved toward a vote on a council resolution to slightly tighten existing sanctions against the mullah regime.

The proposed resolution, circulated to the 15 members of the council late last week, hit a snag yesterday as the U.N. ambassador of the Arab member of the Security Council, Libya’s Giadalla Ettalhi, said his country will oppose it. Iran’s U.N. ambassador, Mohammad Khazaee, told reporters meanwhile that his country would not comply with the resolution and that it does not intend to heed the council’s demand to suspend enrichment.

The State Department’s spokesman, Tom Casey, said yesterday’s meeting in Washington was gathered to talk “about the current resolution, which has been put forward at the U.N. — and we hope to see passed very shortly — as well as to look at additional steps.”

Several New York-based diplomats said it was their understanding that no changes are expected in the current resolution, which was agreed on by the five permanent council members weeks ago and which is expected to be presented for a council vote on Friday.

A Washington-based administration official said that yesterday’s meeting was called for several reasons, including the fact that the current State Department political director, Nicholas Burns — who has presided over the administration’s Iran policy — is expected to leave his post soon. The official, who spoke on condition of anonymity, added that the meeting was mostly designed to discuss “the next steps” against Iran. One such measure may be a move to sanction Iran’s Central Bank, which according to an article yesterday in the Wall Street Journal has been assisting Iranian financial institutions currently under economic sanctions.

In past cases, however, once officials in the capitals of the main powers passed a certain stage in negotiations, they left it to their U.N. ambassadors to hash out the final contours of resolutions. That certainly has been the case with the past two resolutions on Iran, the U.N.-based diplomat said. The most recent resolution, however, gave Iran three months to comply with the demand to suspend enrichment, and the Security Council has been unable to address the Iranian intransigence until now, more than a year later.

As for the new proposed measures, “it would not be logical to comply with this resolution,” Mr. Khazaee told reporters summoned to the Iranian U.N. mission yesterday, according to Bloomberg News, adding that Iran does “not see any reason to suspend our enrichment.” While “no one can say sanctions are not hurting anybody,” he said, “we have learned to live with that.”