* U.S. sees initial deal with Iran as close

* Nuclear talks resume in Geneva on Nov. 20

* Sanctions relief "way south" of figures being reported (Adds comment from top Iranian negotiator)

By Lesley Wroughton

WASHINGTON, Nov 15 (Reuters) - Major powers and Iran are getting closer to an initial agreement to curb Iran's nuclear program, a senior U.S. official said on Friday, adding it is "quite possible" a deal could be reached when negotiators meet Nov. 20-22 in Geneva.

But the official and Iranian Deputy Foreign Minister Abbas Araqchi both said they expected next week's talks to be "tough", and Araqchi said that there would be no deal unless the Iranian people's "rights" were guaranteed.

"For the first time in nearly a decade we are getting close to a first-step ... that would stop the Iranian nuclear program from advancing and roll it back in key areas," the official told reporters on condition of anonymity.

"I don't know if we will reach an agreement. I think it is quite possible that we can, but there are still tough issues to negotiate," the official said.

The official said EU foreign policy chief Catherine Ashton and Iranian Foreign Minister Javad Zarif were to meet on Nov. 20 in Geneva. They will be joined later the same day by a wider group known as the P5+1 comprising Britain, China, France, Germany, Russia and the United States. The talks are likely to last through Nov. 22, the official said.

Araqchi, a senior member of Iran's negotiation team, was quoted as saying by Mehr News Agency, "The expectation is that we will have tough talks, and unless the rights of the Iranian people are guaranteed, an agreement will not be reached."

The talks will seek to finalize an interim deal to allow time to negotiate a comprehensive, permanent agreement that would end a 10-year deadlock and provide assurances to the six powers that Iran's atomic program will not produce bombs.

Iran has denied that it wants to develop atomic weapons capability and insists its nuclear ambitions are limited to the peaceful generation of electricity and other civilian uses.

Negotiations last week in Geneva ended without an agreement, although the sides appeared to be close to a deal.

U.S. President Barack Obama has urged skeptical U.S. lawmakers not to impose new sanctions on Iran while talks continue and called for a pause in U.S. sanctions to see if diplomacy can work.

WHITE HOUSE APPROACH

In addition to lobbying lawmakers, the White House this week also contacted progressive groups supportive of diplomacy with Iran to make sure they stay aligned with the Obama administration's approach, a source close to the matter said.