OCCUPIED JERUSALEM: German Chancellor Angela Merkel has urged Israeli Prime Minister Benjamin Netanyahu not to order a military strike against Iranian nuclear sites, the newspaper Haaretz reported on Friday.

The article, citing an Israeli official on condition of anonymity, said Merkel had called Netanyahu 10 days ago amid a wave of reports of an imminent Israeli attack, to give a "clear message as to her opposition" to such action.

Merkel urged Netanyahu to "give more time for sanctions and diplomacy to work," and warned of the consequences of such an attack for security in the Middle East.

A spokesman for Netanyahu refused to comment on the report or to confirm the conversation had taken place.

Israel and its main ally the United States accuse Iran of seeking to develop an atomic arsenal, but Tehran insists its nuclear programme is for civilian purposes only.

Netanyahu told a visiting US congressman last Friday that Iran was speeding up its quest for nuclear weapons in defiance of international sanctions.

The Haaretz article described the phone call as "exceptional" given the "almost complete disconnect" for two months between Merkel and Netanyahu after a sharp disagreement over Israeli settlements and the Palestinian issue.

Deputy government spokesman Georg Streiter told a Berlin news conference he could "not confirm (the information in) this article," reminding that Berlin did not believe in a military solution to the Iran nuclear issue.

Merkel also said an Israeli attack would have severe consequences for the European Union and that international sanctions, which were taking their toll on Iran, should be strengthened and given time to work, Haaretz wrote.

Iran has doubled its capacity to produce enriched uranium at its underground Fordo plant, according to an International Atomic Energy Agency (IAEA) report released late on Thursday.

The IAEA also accuses Iran of frustrating UN inspection of its Parchin plant, where it suspects tests of explosives that could be used in a nuclear warhead were carried out, by scrubbing it clean.

Netanyahu said on Thursday he would present to the UN the "truth about the terror regime of Iran" at his General Assembly address in late September.