BRUSSELS (AP) - Representatives of six world powers urged Iran on Friday to accept a UN plan aimed at delaying its ability to build a nuclear weapon, as the head of the UN nuclear watchdog agency warned Tehran not to miss the opportunity to resolve the dispute. An EU official said there was no mention of imposing sanctions against Iran for its refusal to halt nuclear enrichment activities at the meeting of senior diplomats from the UN Security Council's five permanent members plus Germany.

"These things are a matter of timing, and this was not the right time for it,'' said the official who asked not to be named because of the sensitivity of the matter.

The talks in Brussels involved political directors - foreign ministry officials below ministerial level. The United States was represented by Undersecretary of State William Burns, and Russia by Deputy Foreign Minister Sergei Ryabkov. The talks came just a day after a day after President Barack Obama said the six nations will develop a package of serious new punitive measures in coming weeks. He did not give details.

On Wednesday, Tehran indicated it would not export its enriched uranium for further processing, effectively rejecting the latest plan brokered by the International Atomic Energy Agency and aimed at delaying Iran's ability to build a nuclear weapon. Under the IAEA plan, Iran would export its uranium for enrichment in Russia and France where it would be converted into fuel rods, which would be returned to Iran about a year later.