Arab governments are privately expressing their concern to Washington about the emerging terms of a potential deal aimed at curbing Iran’s nuclear program, according to Arab and U.S. officials involved in the deliberations.

The direction of U.S. 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 U.S. nuclear umbrella to Middle East allies to counter any Iranian threat.

'At this stage, we prefer a collapse of the diplomatic process to a bad deal,'

- Arab official

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.

Arab officials said a deal would likely drive Saudi Arabia, for one, to try to quickly match Iran’s nuclear capabilities.

"At this stage, we prefer a collapse of the diplomatic process to a bad deal," said an Arab official who has discussed Iran with the Obama administration and Saudi Arabia in recent weeks.

The Obama administration initially said its policy was to completely dismantle Tehran's nuclear infrastructure as a means to protect Washington's Mideast allies.

Now, however, U.S. officials say it is no longer plausible to eliminate all of Iran’s nuclear infrastructure, suggesting that any final deal would leave some nuclear capability in place. Iran denies that it is seeking to build a nuclear bomb, but a final deal providing for nuclear enrichment capacity could prompt a competition.

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.

U.S. officials have declined to publicly disclose terms of the deal being negotiated with Iran. But they stress that they have closely consulted with Washington’s Arab allies about the diplomatic process.

The Obama administration believes an agreement with Iran will curtail the potential for a nuclear arms race in the Mideast, rather than fuel one.

"Only a good negotiated solution will result in long-term confidence that Iran won't acquire a nuclear weapon," a senior U.S. official said. "Given Iran already has the technical capability, our goal has always been to get to one-year breakout time and cut off the four pathways under a very constrained program."

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