TEL AVIV (Reuters) - U.S. Secretary of State John Kerry is committed to doing "anything he can" to narrow differences with Iran over its nuclear program, a senior State Department official said on Friday shortly before Kerry headed to Geneva for talks.

"This is a complex process," the official said in Tel Aviv where Kerry was meeting Israeli Prime Minister Benjamin Netanyahu who has concerns about any deal with Iran. "As a member of the P5+1, he is committed to doing anything he can (to) help narrow these differences," the official added.

The official said Kerry had decided to break from a Middle East visit to go to Geneva at the invitation of Catherine Ashton, the European Union's foreign policy chief.

(Reporting by Lesley Wroughton)