Iranian Foreign Minister Abbas Araghchi said discussions mediated by Oman on the Strait of Hormuz were moving toward a final stage.
In a Telegram message, Araghchi said he had described the talks to Iran's cabinet as being at a final stage or moving toward implementation.
The discussions concern the future management and security of the Strait of Hormuz, a major energy-shipping route.
US President Donald Trump said a new round of US-Iran negotiations would begin on Monday afternoon.
Trump said he had paused a planned military operation against Iran before announcing the proposed talks.
He claimed that a basic framework for an agreement concerning the Strait of Hormuz and Iran's nuclear programme had already been formed.
Trump also claimed that Iran and US regional partners had asked him not to proceed with military action because they believed an agreement was possible.
An Iranian semi-official outlet rejected Trump's assertion that Tehran had asked Washington to halt an attack.
Trump said he did not want to set a deadline for a possible agreement.
He did not identify the location of the proposed Monday meeting or the people expected to take part.
Iran's acting defence minister Majid Ebn al-Reza said Tehran regarded every threat from its adversaries as real and credible and would neither be unprepared nor inactive.
The terms, format and outcome of any prospective US-Iran engagement remain unspecified.