Oman and the United Arab Emirates have said that Gulf Arab states want direct talks with Iran to help resolve the crisis provoked by Tehran's nuclear programme.
They also strongly backed European efforts for a negotiated settlement.
Yusuf bin Alawi bin Abdullah, the Omani foreign minister, said after talks on Monday with his visiting German counterpart, Frank-Walter Steinmeier, that Europe could count on the Gulf states' support to help end the standoff.
"We expressed our great respect for the German side for its constant efforts to achieve a peaceful resolution that is acceptable for all the parties concerned," he said.
"We strongly support these efforts and are committed to continuing close consultations with the German side on this question."
Hamad bin Mohammad al-Rashdi, the information minister, told reporters travelling with Steinmeier, who began a Gulf visit on Saturday, that Oman wanted to do what it could to avert a confrontation between Tehran and the West.
Asked whether a Gulf Arab delegation might visit Tehran soon, Rashdi said this was still being discussed.
The foreign minister of the United Arab Emirates noted after talks with Steinmeier in Abu Dhabi later on Monday that the six Gulf states had agreed in December to send a delegation to Tehran to "tell the Iranians about our fears".
"The Iranians have to be patient and recognise our fears," Sheikh Abdullah bin Zayed al-Nahayan said, adding that these included the potential environmental hazards to the Gulf of an Iranian nuclear reactor.
Sheikh Abdullah (R): Iran must be
patient and recognise our fears
He did not offer a new timetable for the initiative and none of the Gulf countries are calling the initiative mediation.
Steinmeier said that Sheikh Abdullah had also shared his fears about the spectre of an Iranian nuclear bomb and said the involvement of Iran's neighbours in the region was key at this juncture in the negotiations.
"I think we have an occasion to step up our common efforts to reach an agreement soon. That requires a reliable message from the Iranian leadership that they really want to return to the negotiating table," he said.
Iran's government reiterated on Monday that its uranium enrichment programme was not up for negotiation, again rejecting European efforts to secure a halt to the sensitive nuclear work.
Tehran says it only wants to make civilian reactor fuel, a right enshrined by the nuclear Non-proliferation Treaty and overseen by the International Atomic Energy Agency.
Meanwhile, US diplomats are pushing Arab Gulf countries to boost intelligence ties with Washington and expand defences against ballistic missiles and chemical weapons, in what analysts call an effort to prepare for retaliation in case of a US-led attack on Iran.
A slew of high-level US officials have been travelling through the region to persuade the countries to take those steps.
"We are jointly working on significant enhancements to a number of defensive capabilities in the region"
John Hillen, US assistant secretary, political-military affairs
But US military officials and analysts in the region say the US State Department's efforts have not, so far, brought about a bolstered security presence focused on Iran.
"The tension with Iran is still diplomatic, not military," said Commander Jeff Breslau of the US Navy's Bahrain-based 5th Fleet.
And, even as the effort gets under way, some are urging Gulf governments to avoid openly provoking Tehran, a key trading partner that sits just across the Gulf.
US State Department officials touring the region in recent weeks include John Hillen, the assistant secretary for political-military affairs, and Robert Joseph, undersecretary for arms control and international security.
Both focused on rallying Gulf Arab support for US efforts to halt Iran's nuclear programme, while urging closer military and intelligence ties with Washington.
"We are jointly working on significant enhancements to a number of defensive capabilities in the region," Hillen said.
Hillen said the talks included discussions on sophisticated new defences against Iranian ballistic missiles, the monitoring of suspicious transactions and the interdiction of shipments of nuclear technology headed to Iran.
But he provided few details.
In April, Joseph visited Bahrain, the United Arab Emirates, Oman, Kuwait, Saudi Arabia and Qatar, urging them to upgrade defences against chemical and biological weapons.
Joseph also requested help monitoring financial restrictions with Iran and closing what he described as Iranian "front companies" seeking nuclear technology.
Hillen said the co-operation goes beyond the existing Patriot missile defence batteries in Qatar, Kuwait and Saudi Arabia and the US Navy's Gulf patrols that seek to track rogue nuclear shipments.
The range of Iran's Shahab-3 ballistic missile reaches Gulf countries and beyond, including Turkey and Israel.