WASHINGTON (Reuters) - Iran is on the verge of reaching a stage where talks can be held, US Defense Secretary Mark Esper said on Tuesday, while Iranian Foreign Minister Mohammad Javad Zarif said he was suspending his country's nuclear research commitments.

"Iran is the biggest threat to the region," Esber said at a panel discussion at the Royal United Services Institute in Britain.

The Reuters news agency quoted a US defense official as saying that Washington still believes that the application of sanctions on Iran is important to get it to sit at the negotiating table.

Ministers from the United States and France are discussing coordination between the navies to ensure free shipping in the Gulf, the official said.

The comments come days after US President Donald Trump left the door open for a possible meeting with his Iranian counterpart Hassan Rouhani at the next UN General Assembly in New York.

On Thursday, the chairman of the US Joint Chiefs of Staff, Gen. Joseph Danford, said they had enough troops to deter Iran and its proxies from attacking his country or its interests in the region.

At the same time, he said Washington had no deterrent against attacks on its regional partners such as the UAE and Saudi Arabia.

Zarif announces suspension of Iran's nuclear research commitments (Anatolia)

Reduced obligations
In return, the Iranian Foreign Ministry said that the minister informed the European Union's foreign policy coordinator Federica Mogherini to stop Tehran's commitments in the field of nuclear research.

At the same time, the Iranian ministry confirmed its readiness to reverse those steps if the other parties implement their commitments under the nuclear agreement.

Zarif stressed that the measure comes within the rights of Iran and in response to the US withdrawal from the nuclear deal.

In his letter to Mogherini, he noted that Iran would continue its negotiations with the partners of the nuclear agreement at all levels and was ready to back down from its steps if the other parties implemented their commitments.

Iran announced earlier that the third step would include work on developing centrifuges.

For its part, the European Union renewed its call for Tehran to reverse the decision to reduce its commitments to the nuclear deal. He called on her to refrain from taking any steps that contradict the terms of the agreement.

On Friday, Germany said it was not too late for Iran to change course. "We urge Iran not to aggravate the situation," the foreign ministry spokesman said. "There is still time for it to abandon the wrong course it is taking."