TEHERAN- Iran's Foreign Ministry Spokesman Esmaeil Baghaei said Tuesday that the US new sanctions on Teheran run against bilateral nuclear talks, reported the Iranian Students' News Agency.

Baghaei made the remarks in a speech during the 36th Tehran International Book Fair in the Iranian capital while responding to the US enforcement of fresh sanctions against Iran amid the two countries' indirect negotiations brokered by Oman, the report said.

Baghaei slammed US officials for their "contradictory" remarks about what they sought to achieve in the talks, stressing that the other side should regulate their minds and refrain from making contradictory comments.

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Baghaei said Iran is steadfast in the negotiations and its positions are "determined, clear and unchangeable," adding that Iran has entered the talks seriously as "we have always entered negotiations to achieve results, not to use talks as a tool to waste time."

He emphasized that in the negotiation process, Iran seeks to preserve its nuclear achievements, "which have been based on the country's needs," and remove the "cruel" sanctions against the Iranian nation.

On Monday, the US Department of State said it was sanctioning three Iranian nationals and one Iranian entity "with ties to Iran's Organization of Defensive Innovation and Research."

On Tuesday, the department said in a statement that Washington was sanctioning an international network facilitating the shipment of millions of barrels of Iranian crude oil.

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The new sanctions came as the delegations of Iran and the United States on Sunday held the fourth round of their indirect talks on Teheran's nuclear program and the removal of Washington's sanctions in the Omani capital Muscat.

The first and third rounds were held in Muscat on April 12 and 26, and the second in Rome on April 19.