European Union governments could approve a new package of sanctions against Iran in the coming weeks, EU diplomats said on Thursday, a day after a United Nations report revealed that Tehran has worked to design atom bombs.

Preliminary discussions among EU capitals on new measures have already started and diplomats said plans may be formalized by the Dec. 1 meeting of EU foreign ministers in Brussels.

"Experts are discussing a number of options on the table but it is difficult to foresee the outcome of the debate," one EU diplomat said, adding it was not clear when consensus might be found. Another EU diplomat said he expected a formal decision to be reached on Dec. 1.

EU sanctions would be a significant part of Western efforts to ratchet up pressure on Tehran in the wake of the UN watchdog's report this week that laid bare a trove of intelligence suggesting Iran is seeking nuclear weapons.

Western governments would prefer a more united approach toward Tehran through sanctions adopted by the United Nations, but such moves look unlikely in the face of opposition from Russia and China at the UN Security Council.

The United States and its European allies say Iran is trying to build bombs under cover of a civilian nuclear program. The major oil producer denies this, saying it needs nuclear technology to improve its electricity supply for a rapidly growing population.

Israel, which Iran refuses to recognize, sees a nuclear Iran as a threat to its existence and has said all options are on the table in confronting Tehran, including a military one. But it remains publicly committed to a world power strategy of increased diplomatic pressure and sanctions against Iran.