(Bloomberg) — Iran’s insistence on an immediate lifting of
United Nations sanctions is a main obstacle to securing a
framework agreement on its disputed nuclear program by March 31,
five European and U.S. diplomats said.

The Western powers negotiating with Iran have proposed
lifting UN sanctions in four to six years, according to the
officials who asked not to be named, in line with diplomatic
rules. Some sanctions may remain in place for as long as a
decade, they said.

The Chinese foreign minister, Wang Yi, is expected to offer
new proposals when he arrives on Sunday morning, according to
two people involved in the talks.

Talks between the Persian Gulf nation, which holds the
world’s fourth-largest oil reserves, and six world powers
continued Sunday for a fifth day in Lausanne, Switzerland.
Sunday’s meetings began with U.S. Secretary of State John Kerry
meeting Iranian Foreign Minister Mohammad Javad Zarif. They were
joined by U.S. Energy Secretary Ernest Moniz and Ali Akbar
Salehi, Iran’s top scientist in charge of its nuclear program.

The sides are working against a self-imposed end-of-March
deadline needed to set up a comprehensive deal by July 1.

‘Really Serious’

Iran continues to insist that all sanctions must be lifted
once it agrees to place curbs on its nuclear activities. The UN
Security Council, the U.S. Treasury Department and the European
Union have all levied economic sanctions on the country over its
nuclear program.

Zarif told reporters on Saturday that while headway had
been made on sanctions relief, there was more to do.

“They have realized that sanctions pressure and an
agreement will not go together,” Zarif said. “I see that
Germany and France are really serious about reaching an
agreement.”

Iranian President Hassan Rouhani said the removal of
sanctions must be “a fundamental part of this agreement” and
that it was “the other side’s turn to take the final steps,”
the Fars news agency reported Sunday.

The European and U.S. approach focuses on first suspending
and then permanently removing sanctions over the lifetime of a
deal. Oil sanctions could be lifted within months of an
agreement if Iran agrees on a deal that limits its nuclear
capacity and allows for broader international verification, one
European diplomat said.

“Our president has expressly said that the removal of
sanctions has to take place immediately when an agreement is
reached,” Iran’s Supreme Leader, Ayatollah Ali Khamenei said
earlier this month in his New Year address to the nation. “The
U.S. keeps repeating that we’ll sign a deal with Iran and see if
it abides, then we’ll remove the sanctions. This is wrong and
unacceptable.”

Russia’s View

Earlier on Saturday, Russian deputy foreign minister Sergei
Ryabkov said that narrowing disagreements put chances of meeting
the March 31 deadline at “significantly higher than 50
percent.”

“If we don’t manage to agree this time, this shouldn’t
lead to a complete reassessment,” because the deadline for a
final deal is not until the end of June, Ryabkov said.

Parties are close to an agreement on turning Iran’s Fordo
enrichment facility into a medical isotope production center, an
official at the talks said. While Iran would be prohibited from
enriching uranium at Fordo, centrifuges would be allowed to
produce molybdenum and other isotopes, according to the
official’s account.

French Foreign Minister Laurent Fabius and German Foreign
Minister Frank-Walter Steinmeier, along with European Union
foreign policy chief Federica Mogherini, joined Saturday’s talks
with Kerry at the Beau Rivage Palace Hotel on the shores of Lake
Geneva. Russian Foreign Minister Sergei Lavrov is due in
Lausanne on Sunday.

China in an earlier round of talks this month proposed ways
to address lifting UN sanctions.

To contact the reporters on this story:
Henry Meyer in Lausanne, Switzerland at
hmeyer4@bloomberg.net;
Kambiz Foroohar in Lausanne, Switzerland at
kforoohar@bloomberg.net;
Indira A.R. Lakshmanan in Lausanne, Switzerland at

ilakshmanan@bloomberg.net

To contact the editors responsible for this story:
Andrew J. Barden at
barden@bloomberg.net
Amy Teibel