The White House confirmed Tuesday that the talks between the United States and Iran scheduled for Saturday in Oman will be direct, after Tehran rejected any alternative format for indirect negotiations.

US President Donald Trump announced the talks on Monday, after repeatedly threatening Iran with military action if it did not accept a new agreement since returning to the White House in January.

Washington confirmed that Steve Witkoff, Trump's special envoy, will lead the negotiations. "Special Envoy Witkoff will be there," State Department spokeswoman Tammy Bruce told reporters.

Trump said Saturday's planned talks in Oman would be direct, but Iranian Foreign Minister Abbas Araghchi reiterated Tehran's position on Tuesday that the negotiations should be indirect, citing what he described as US pressure and threats. Araghchi told the Islamic Republic News Agency (IRNA) that "there will be no negotiations in any other form. Indirect negotiations ensure real and effective dialogue."

He added that the talks will be led by him and US President Donald Trump's Middle East envoy, Steve Witkoff, with Omani Foreign Minister Badr al-Busaidi mediating.

White House Press Secretary Caroline Leavitt denied Iran's insistence that the discussions would be indirect.

"Saturday's talks will be live," Levitt added, noting that she had no further details.

A source familiar with US plans for the talks confirmed that the discussions will be comprehensive in their quest to reach a nuclear agreement and will not be technical in nature. The source added to Reuters: "Things are still in the making."

This came as US Energy Secretary Chris Wright warned of tightening sanctions on Iran if it does not reach an agreement with President Donald Trump regarding its nuclear program.

"I certainly expect very severe sanctions on Iran, and I hope they will push it to abandon its nuclear program," he added in an interview with CNBC.