U.S. National Security Adviser Susan Rice assured Israel at high-level talks on Thursday that Washington remained determined to stop Iran developing nuclear arms, the White House said.

"The U.S. delegation reaffirmed our commitment to prevent Iran from acquiring a nuclear weapon," said a White House statement released after talks in Jerusalem between Rice, Prime Minister Benjamin Netanyahu and senior officials from both sides.

U.S. National Security Adviser Susan Rice assured Israel at high-level bilateral talks on Thursday that Washington remained determined to stop Iran developing nuclear arms, the White House said.

"The U.S. delegation reaffirmed our commitment to prevent Iran from acquiring a nuclear weapon," said a White House statement released after talks in Jerusalem between Rice, Prime Minister Benjamin Netanyahu and senior officials from both sides.

The reformist Ghanoon daily did not appear on newsstands in Tehran on Thursday after the judiciary accused it publishing false reports and shut it down.

Ghanoon, meaning "law" in Persian, is the latest victim of ever-increasing bans being slapped on the media despite President Hassan Rouhani vowing to ease such restrictions when he took office in August.

Pakistan Tuesday strongly denied that kidnapped Iranian border guards were ever on its soil, amid fresh efforts to improve fractured ties before Prime Minister Nawaz Sharif's visit to Tehran.

Relations between the neighbors hit a low following the kidnapping by Sunni extremists of five Iranian border guards from Iran's Sistan-Baluchestan province, which adjoins Pakistan, in February.

Iran's annual oil and gas fair opens in Tehran on Tuesday, with 600 foreign companies seeking to position themselves for a return to large-scale operations if international sanctions are lifted.

With some of the world's biggest oil and gas reserves, the industry is the cornerstone of Iran's economy, but it was heavily hit by an American and European embargo on the energy and banking sectors in 2012.

A delegation from the International Atomic Energy Agency has arrived in Iran to visit two nuclear sites ahead of the next round of political talks with world powers next week.

After meeting officials from the Atomic Energy Organization of Iran on Monday the IAEA team will travel to Saghand uranium mine and the Ardakan yellow-cake production site, the official IRNA news agency said.

President Hassan Rouhani promised Thursday to improve labor conditions for Iran's workers, particularly by increasing job security in the ailing economy and banning gender discrimination.

Ironically, Rouhani's government had refused to issue a permit for workers to rally in the capital to mark International Labor Day, as was the case with the administration of former president Mahmoud Ahmadinejad.

Iran rejected an annual U.S. report that keeps Tehran on a list of state sponsors of terrorism as reflecting double standards, media reports said Thursday.

The foreign ministry was reacting to a State Department report released Wednesday that kept Cuba, Iran, Syria and Sudan on its list of so-called state sponsors of terrorism.

Iran has overturned a ban on reformist newspaper Ebtekar, after it was shut down for "spreading lies," media reports said on Tuesday.

The daily was banned on Saturday over a Thursday headline to an article about the replacement of Iran's prisons chief following reports of violence against jailed political activists.

Iran on Tuesday defended Syria's June presidential election, saying the vote could end the three-year-old civil war ravaging its close ally.

The response came as President Bashar Assad registered to stand in the June 3 vote, which is widely expected to return him to office despite the grinding conflict.