Iran said a "massive cyber attack" has been detected on its nuclear facilities and that they believe U.S., Israel and Britain are behind it. Iran's chief negotiator Saeed Jalili addressed a news conference after a meeting in Istanbul April 14, 2012 and said progress was made during talks with the world powers who are disputing the country's nuclear program. Reuters

Iran indicated Wednesday that it will seek the lifting of sanctions over its nuclear program in upcoming talks with world powers in Baghdad May 23, though it maintained that it has the right to develop nuclear energy for peaceful uses.

We continue to be optimistic about upcoming negotiations, Deputy Foreign Minister Mohammad Mahdi Akhondzadeh said in a speech to a nuclear non-proliferation conference in Vienna, Reuters reported, though he added: There should be no doubt that the great nation of Iran...will never abandon exercising its inalienable right to peaceful use of nuclear energy and technology.

Iran will meet with the five permanent members of the U.N. Security Council -- the U.S., U.K., France, Russia and China -- as well as rotating member Germany, in Iraq's capital later this month.

Iran has been hit by numerous economic sanctions targeting its banking and energy sectors over its nuclear energy program, which the U.S. and its allies believe is a cover for developing atomic weapons.

An adviser to Iran's Supreme Leader Ayatollah Ali Khamenei specifically mentioned the sanctions in a televised interview with Iranian state media Wednesday.

Our expectation is the lifting of sanctions, Gholam-Ali Haddad Adel said in reference to Iran's aims in the upcoming nuclear talks, Al Jazeera reported.

The U.S., however, does not appear to share in Iran's optimism regarding the sanctions.

No one's talking about any sanctions being reversed or canceled at all, said State Department spokesman Mark Toner on April 16, just after the Baghdad nuclear summit was announced, the Associated Press reported.

U.S. officials have made it clear that it will only rescind the sanctions if Iran ceases uranium enrichment, which Iran has said would interfere with its professed goal of peaceful nuclear energy development.

Secretary of State Hillary Clinton said the possibility of lifting sanctions on Iran was hypothetical, shortly after Toner's remarks.

We have to see what the Iranians are willing to do, then we have to make sure they do it, and then we have to reciprocate. That's what a negotiation is all about, Clinton told CNN in an April 19 interview.