"The President and the Prime Minister agreed on the importance of Iran strictly abiding by its obligations under the international nuclear non-proliferation regime," said a statement by the White House.

Washington is leading an effort to toughen sanctions on Iran over its nuclear programme, which the US and allies say is aimed at producing weapons, a charge Tehran has consistently denied.

The statement also said Najib agreed that Iran should be sent a "clear signal".

"The two Leaders also agreed on the need for the international community to send a clear signal to Iran that while it has the right to develop peaceful uses of nuclear energy, Iran should not use this right to develop nuclear weapons capability as stated in UNSC and IAEA resolutions."

It also stated Malaysia's readiness to cooperate with the US in Afghanistan for "capacity building" through the training of police, military personnel and civilian administrators.

The US efforts have however met with strong opposition from big powers such as China, Russia, Latin-American countries and Turkey. UN security council members Brazil, Turkey and Lebanon, alongside permanent member China, are expected not to support the next round of sanctions against Iran.

The US's Arab allies have also called for dialogue with Iran, with the Arab Summit in Libya last month showing signs that Washington's strategy on Iran was less likely to get Arab support, especially amid growing fears of Israel's unchecked nuclear arsenal.

Turkish prime minister Recep Tayyip Erdoğan (left) has repeatedly spoken out against attempts by the US and its allies to impose sanctions on Iran, saying that they should instead focus on Israel whose nuclear weapons arsenal has been immune from international scrutiny.

Israel has stayed away from the current nuclear security summit in Washington, fearing Turkey's plan to file a motion demanding that Tel Aviv open its nuclear facilities for international inspection.

Malaysia's stance is believed to be the first open support by a Muslim government to US efforts to isolate Iran.

The move is expected to attract strong reactions at home, coming as it does after the government was severely criticised over its refusal to renew the contract of a veteran diplomat last  year for voting against a resolution to rebuke Iran.

Mohammed Arshad Manzoor Hussain, the rotating head of the  International Atomic Energy Agency (IAEA) and a diplomat with 35 years of experience, was recalled to Kuala Lumpur after he voted in line with the position of members of the Non-Aligned Movement (NAM), which has opposed attempts to isolate fellow NAM member Iran.

Najib's support for Washington is also expected to fuel speculation over the role of a consultancy firm, Apco Worldwide, in the changing foreign policies of the Malaysian government, which in the past has sided with developing countries and spoken out against US hegemony.

Apco has been in the centre of the storm after revelations by Opposition Leader Anwar Ibrahim over its close links with senior Israeli officials.

On March 22, PAS central committee member Mohamad Sabu questioned whether the firm had a hand in the decision to terminate Arshad's contract.

"As the decision to sack (Arshad), which is an action that is pro-US and pro-Israel, was made at a time when the prime minister and the BN government looked up to Apco for advice and guidance, we cannot help but wonder whether it was the result of the Zionist-dominated firm's influence," said Mohamad Sabu.

Former prime minister Dr Mahathir Mohamad, in a blog posting last December, had also lent his opposition against Arshad's removal.

"We have never supported any sanction (against Iran). But now, our envoy is recalled to be questioned why he did not support the US," he wrote.