United States' President Donald Trump announced on Monday that any military strikes against Iranian energy sites will be held off for five days after the two sides held "productive conversations" over the weekend, a comment that instantly pushed up stock futures and drove down oil prices.

However, Iran denied any such contact soon after Trump's remarks, saying that there had been no negotiations, "direct or indirect" with Washington as described by Trump, according to Iran's semi-official Fars news agency.

Trump's announcement on social media marked a stunning about-turn from his previous ultimatum that the US would strike Iranian power plants if Tehran did not reopen the Strait of Hormuz by Monday night.

In a telephone interview with Fox Business Network later on Monday, Trump said that Iran badly ?wants to ?make a deal and that could come within five ?days or less. He said the most recent talks between ?US envoys Steve Witkoff and Jared Kushner and ?their counterparts ?took place on Sunday night.

A reporter for the US news outlet Axios said representatives of Turkiye, Egypt and Pakistan had met separately with Witkoff and Iranian Foreign Minister Abbas Araghchi. The reporter, Barak Ravid, cited an unnamed US source as saying the discussion was about ending the war and resolving all outstanding issues.

On Sunday, Araghchi said that the Strait of Hormuz remained open, but ships were hesitating to use the vital waterway because insurers feared the "war of choice" initiated by the US and Israel, as the conflict entered its fourth week.

Meanwhile, the Islamic Revolutionary Guard Corps pushed back against what it said were false claims by Washington that Tehran intended to destroy water desalination plants in the Gulf region, Al Jazeera reported on Monday.

"What we have done is to announce our decision that in the event of an attack on power plants, Iran will retaliate by targeting the power plants of (Israel) and the power plants of the countries in the region that supply power to American bases, and at the same time, the economic, industrial and energy infrastructure in which the Americans are shareholders," the IRGC was quoted as saying by Al Jazeera.

The Iranian Foreign Ministry also issued a statement on the Strait of Hormuz, published by Mehr News Agency on Monday.

The statement called the US-Israeli strikes against Iran a clear violation of Article 2(4) of the UN Charter.

"In exercising its inherent right of self-defense against the aggressor parties, Iran has not only targeted US military bases and facilities in the region, but has also adopted a series of measures to prevent the aggressors and their supporters from exploiting the Strait of Hormuz to advance … their hostile objectives against Iran," the statement said.

Meanwhile, several explosions were reported in Iran early on Monday.

According to Tasnim News Agency, the US struck residential neighborhoods in Khorramabad, western Iran, killing nine civilians.

Al Jazeera reported a US-Israeli strike on a radio station in the Iranian city of Bandar Abbas, killing one person. The activation of air defenses was heard in Tehran, while in Isfahan, Karaj and Ahvaz, massive explosions were heard.

Israel has also been accused of expanding its ground invasion in southern Lebanon, after the Israeli Air Force blew up a bridge over the Litani River on Sunday.

Lebanese President Joseph Aoun called Israel's latest attack on his country a "collective punishment" of Lebanese civilians and a dangerous escalation.