Officials from six world powers and Iran are meeting to discuss the country's controversial nuclear program, in the latest talks to address a decade of concerns that Iran is working to develop a nuclear weapon.
U.S. Secretary of State John Kerry is urging Iran to move towards a diplomatic solution on its nuclear ambitions.
Tuesday's meeting in Almaty, Kazakhstan, includes the so-called P5+1 group of nations -- the United States, Britain, France, Russia, China and Germany -- and is not expected to produce any major breakthroughs.
The world powers are expected to offer to ease some sanctions against Iran if its agrees to halt some of its enrichment activity.
Iran says its nuclear program is for peaceful purposes, but many nations around the world are concerned it is actually aimed at building nuclear weapons.
Kerry, who met Tuesday with his German counterpart in Berlin, "expressed hope" that "Iran itself will make its choice to move down the path of a diplomatic solution."
Kerry said previously in London that "an Iran having a nuclear weapon, in that region, and given all that has happened, is simply unacceptable."
He said the United States is prepared to work in "good faith" and "mutual respect" to avoid what he called the "consequences" of a failed deal at Tuesday's talks.
The International Atomic Energy Agency recently said that Iran has begun installing a new generation of centrifuges at its Natanz enrichment plant, a move U.S. officials have deemed "provocative."
The Tuesday meeting is the first in eight months.
Over the past few years, the United Nations Security Council has imposed sanctions on Iran in an effort to pressure it to curb its enrichment program. Several other countries, including the United States, have imposed their own additional measures.