GENEVA, Feb 23 (Reuters) - High-level nuclear negotiations between the United States and Iran resumed in Geneva on Monday as both sides work through technical and political differences to come up with an initial deal by a March 31 deadline.
U.S. Secretary of State John Kerry and Iranian Foreign Minister Mohammad Javad Zarif, as well as U.S. Energy Secretary Ernest Moniz and Iran's atomic nuclear chief Ali Akbar Salehi met for a second day following a two-hour meeting on Sunday.
"Both sides are determined to resolve the remaining issues," a senior Iranian official told Reuters.
"Gaps still remain and the negotiators are trying hard to reach a common point," the official said, describing the atmosphere as "good but very serious."
A senior State Department official said the session would cover "virtually every topic."
Few details of the negotiations have emerged, but the approaching deadline has caused divisions between the United States and one of its closest allies, Israel, which has called the talks "dangerous" and "astonishing." The United States has accused it of distorting Washington's position.
Helga Schmid, political director of the European Union's External Action Service, was also at the table for the Kerry-Zarif meeting on Monday.
The United States and five other major powers - Russia, China, Britain, France and Germany - are seeking to negotiate an agreement with Tehran to end a 12-year standoff over its nuclear ambitions. Iran says it does not intend to develop atomic bombs.
A deal would offer Iran relief from economic sanctions.
With talks mainly between Washington and Tehran, Kerry insisted at the weekend "there is absolutely no divergence" between the United States and the five other powers, with everyone focused on the common goal.
Both sides have said that the presence of Moniz and Salehi at the talks in Geneva reflected the technical nature of the talks, which have reached a sensitive stage, with gaps remaining mostly over Iranian uranium enrichment and the pace of removing sanctions, official said.
Kerry was due to return to Washington late on Monday, in time for a congressional hearing over the State Department's budget rerquest for fiscal 2016. His talks in Geneva are likely to be raised during the testimony. (Reporting by Lesley Wroughton Additional reporting by Parisa Hafezi Editing by Tom Miles and Louise Ireland)