PARIS - Concerns over a final nuclear deal with Iran and civil war in Yemen will top the agenda of talks in Paris on Friday between U.S. Secretary of State John Kerry and Gulf Arab states.

He was joined by Washington's chief Iran negotiator Wendy Sherman and U.S. Secretary of Energy Ernest Moniz, a nuclear specialist.

The Paris meeting will lay the groundwork for a summit next week in Washington and Camp David between U.S. President Barack Obama and the six-nation GCC.

Obama faces a formidable challenge to allay Gulf Arab fears over a nuclear deal with Tehran which is due by June 30.

U.S. officials have told Reuters the Washington summit would help Gulf allies create a region-wide defense system to guard against Iranian missiles and could be accompanied by enhanced security commitments, new arms sales and more joint military exercises.

While in Saudi Arabia on Thursday Kerry said the goal of talks was to "see how we can provide greater assurance to people about the road ahead, as well as build an architecture which allows us to cooperate more effectively."

Washington, however, is mindful that additional defense obligations could carry the risk of the United States being drawn into new Middle East conflicts.

The United States has supported the Saudi-led coalition, which began strikes against the Houthis and forces loyal to ex-president Ali Abdullah Saleh on March 26 with the aim of restoring the government of President Abd-Rabbu Mansour Hadi.

Riyadh fears the Houthis, who are allied to its foe Iran, will dominate Yemen, and that the advance of Shi'ite Houthi fighters into Sunni areas will provoke sectarian fighting that al Qaeda can exploit. Iran has denied Saudi and Yemeni government charges it arms and trains the Houthis. (Reuters)