TEHERAN - Iran's Supreme Leader Ali Khamenei on Saturday denounced as "a lie" US President Donald Trump's recent claim that he sought to use power to ensure peace, citing the Trump administration's support for the killings in the Gaza Strip.

Khamenei made the remarks at a meeting with a large number of teachers in Teheran, while reacting to Trump's comments on wanting peace in the region during his tour of West Asia earlier this week, according to footage of his remarks published on his website.

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"Trump said he wants to use power for peace; he lied. He and other US officials, and US administrations have used power to support the killings in Gaza, for warmongering in any place they can, and to back their mercenaries," the Iranian leader said.

He expressed confidence that with the determination and efforts of regional countries, the United States must and will leave the region.

Earlier this week, Trump visited three Gulf Arab states -- Saudi Arabia, Qatar, and the United Arab Emirates, which are located in West Asia.

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In remarks in the Saudi capital Riyadh on Tuesday, Trump described Iran as the "most destructive force" in the Middle East and accused it of fueling regional instability, vowing that the United States would never let Iran obtain a nuclear weapon.

The trading of accusations between Teheran and Washington comes as the two sides have held four rounds of indirect talks on Teheran's nuclear program and the lifting of US sanctions over the past weeks, with mediation from Oman.