The emerging terms of a deal to curb Iran's quest for a nuclear bomb is striking fear to neighbouring Arab countries in the region.
Concerns are mounting that the US may allow the Iranian regime to continue with its nuclear programme for civilian purposes - and therefore maintain the technology needed to produce nuclear weapons.
The Washington Post newspaper said: "The direction of US diplomacy with Tehran has added fuel to fears in some Arab states of a nuclear-arms race in the region, as well as reviving talk about possibly extending a US nuclear umbrella to Middle East allies to counter any Iranian threat.
"The major Sunni states, including Saudi Arabia, Egypt, the United Arab Emirates and Qatar, have said that a final agreement could allow Shiite-dominated Iran, their regional rival, to keep the technologies needed to produce nuclear weapons, according to these officials, while removing many of the sanctions that have crippled its economy in recent years."
And Arab officials said any deal could drive Saudi Arabia and other states to try to match Iran’s nuclear capabilities.
One Arab official said: "At this stage, we prefer a collapse of the diplomatic process to a bad deal."
The Obama administration initially said its policy was to completely dismantle Tehran’s nuclear infrastructure as a means to protect Washington’s Middle East allies, the paper said.
But it added: "Arab officials have increasingly spoken about a possible nuclear arms race in the Mideast as the negotiations have continued for 18 months, having been extended twice."
Arab leaders said they are committed to supporting the US coalition fighting Islamic State. But they said the campaign is complicated by fears Washington is aligning with Tehran, it added.