US Secretary of State Marco Rubio said on Tuesday that President Donald Trump's administration has not offered Iran sanctions relief in exchange for reopening the Strait of Hormuz, insisting that any easing of sanctions would be tied to Tehran abandoning its nuclear programme.
Testifying before the Senate Foreign Relations Committee, Rubio said sanctions on Iran were imposed because of its nuclear activities and highly enriched uranium stockpile.
"Any sanctions relief is condition-based, which means it has to be in return for the reason why those sanctions were put in place in the first place, which is their nuclear program," Rubio said.
Rubio also disclosed that Iran had agreed to negotiate aspects of its nuclear programme that it had previously refused to discuss, though he cautioned that this did not guarantee a deal. He said reopening the Strait of Hormuz and negotiating over Iran's stockpile of highly enriched uranium were among the conditions being discussed.
Trump has repeatedly said preventing Iran from acquiring a nuclear weapon remains his top foreign policy priority. Iran, meanwhile, has consistently denied seeking a nuclear bomb, maintaining that its nuclear programme is intended for peaceful purposes.
Rubio, who is also Trump's national security adviser, argued that Iran had sought to build up conventional military capabilities as a shield for its nuclear programme, which he said contributed to the administration's decision to launch military action.
The secretary of state was appearing before Congress publicly for the first time since the Iran conflict began four months ago following US and Israeli strikes on Iran. Several lawmakers, including some Republicans, have increasingly questioned the conflict and sought greater clarity on the administration's endgame.
Senator Jeanne Shaheen, the top Democrat on the committee, criticised the administration for failing to adequately consult Congress on the war and said Americans were more concerned about economic issues at home than foreign conflicts.
Rubio's testimony comes as the administration seeks congressional approval for a 30 per cent reduction in foreign affairs spending alongside a 50 per cent increase in military expenditure.
Rubio also indicated that the administration would like to end sanctions waivers granted to countries purchasing Russian oil, saying the exemptions were intended only as temporary measures to stabilise global energy markets after the Iran conflict disrupted supplies.
"We would like to end it as soon as we possibly can because the underlying policy of this country has been to sanction their oil," Rubio told lawmakers.
The US first granted the waiver in March and has extended it twice, most recently until June 17. India is among the countries that have benefited from the exemption.
Rubio said the waivers were designed to ease pressure on global oil markets rather than benefit the US economy, adding that other countries remained more dependent on stable energy supplies.
Rubio also sought to reassure lawmakers that there had been no change in US policy towards Taiwan despite concerns raised in Taipei after last month's summit between Trump and Chinese President Xi Jinping in Beijing.
"The most important thing to understand is we want to see the status quo preserved as-is at this moment. That's our policy, that's what we've said, that's what we continue to say," Rubio said.
He described the relationship as delicate but reiterated that Washington's longstanding position on Taiwan remained unchanged.
Rubio also said the US would re-engage with the global vaccine alliance Gavi amid concerns over Ebola outbreaks in parts of Africa.
He told lawmakers that the decision had been taken several weeks ago, reversing last year's move by the Trump administration to withdraw funding from the organisation.
Gavi helps low-income countries procure vaccines and supports responses to disease outbreaks, including Ebola.
Rubio said the State Department would work towards a resolution that addresses concerns raised by the Department of Health and Human Services while supporting broader US global health objectives.
"We'd like to get this issue resolved in an outcome that's acceptable both to Congress and also to our goals on global health," he said.