Amid forecasts that a
Negotiators have wavered between optimism and gloom since they sat down last Sunday at a luxury hotel here in Lausanne, Switzerland, to work out the outline of a deal to prevent Iran from gaining nuclear weapons capability.
Iranian Foreign Minister Mohammad Javad Zarif ended the week on a high note, saying that the deal was mostly complete and that U.S. Secretary of State
"For many issues, solutions exist, and solutions have been found," Zarif said, according to the Iranian Students News Agency.
Kerry was meeting the Europeans because "more internal coordination was needed before the next round of talks," Zarif said.
Six world powers -- the United States, Britain, France, Germany, Russia and China -- have been negotiating for 18 months with Iran, seeking a deal that would gradually lift economic sanctions on that country in return for restrictions on its nuclear program.
The diplomats, who had considered working through the weekend, plan to return to Switzerland on Wednesday to resume efforts to work out the main elements of a deal before March 31. A final, detailed text would be due by July.
State Department officials confirmed that Kerry plans to meet in Europe this weekend with the French, British and German foreign ministers to discuss the talks. Kerry also spoke on the phone Friday with the Russian and Chinese foreign ministers, spokeswoman Marie Harf said in a statement.
The six-day negotiating round had been "intensive," and "given where we are, it is time for high-level discussions with our partners in these talks," Harf said.
At the White House, spokesman Josh Earnest said President
"These negotiations have been going on for more than a year, and the time has come to strike an agreement, if one can be reached," Earnest said.
The break in the talks, timed to coincide with the Iranian New Year holiday, Nowruz, came as Obama released a videotaped new year's message to the Iranian people, urging them to support the negotiations.
Obama appealed in particular to Iran's young people, telling them that a deal that ends Iran's isolation could lead to a better future for them.
"If Iran's leaders can agree to a reasonable deal, it can lead to a better path -- the path of greater opportunities for the Iranian people," he said. "More trade and ties with the world. More foreign investment and jobs, including for young Iranians. More cultural exchanges and chances for Iranian students to travel abroad.
"In other words, a nuclear deal now can help open the door to a brighter future for you -- the Iranian people, who, as heirs to a great civilization, have so much to give to the world," Obama said.
Iran's leaders "have a choice between two paths. If they cannot agree to a reasonable deal, they will keep Iran on the path it's on today -- a path that has isolated Iran, and the Iranian people, from so much of the world, caused so much hardship for Iranian families, and deprived so many young Iranians of the jobs and opportunities they deserve," he added.
The White House also released a separate statement in which Obama called on Iran to release three Americans imprisoned there, including Washington Post reporter Jason Rezaian, and to help the United States find Robert Levinson, a former FBI agent and CIA contractor who disappeared eight years ago. Some U.S. officials believe Levinson has died.
The Obama administration has been under pressure from
The break comes amid some signs of divisions among the Western governments involved in the negotiations. French officials have become more public recently in asserting that Iran needs to give more if the agreement is going to be effective in keeping Tehran from obtaining a nuclear weapon.
The goal of the talks has been to limit Iran's nuclear efforts so that it would remain a year away from being able to put together enough fuel for a single bomb and impose strict monitoring systems that would prevent the Iranians from cheating.
Unresolved issues include how quickly sanctions would be lifted, especially those imposed by the United Nations; how much nuclear research and development Iran would be allowed to do; how many years any agreement would last; and the plans for monitoring and inspections.
Diplomats say some European officials also have expressed unhappiness that what used to be a seven-way conversation has evolved in the last few months into largely an Iran-U.S. negotiation.
Another complication is discussion of which countries will get lucrative commercial contracts to modify Iran's nuclear program once a deal is concluded, according to people involved in the talks.
Kerry also issued a statement Friday morning expressing condolences to Iranian President