Secretary of State Mike Pompeo held out the possibility on Tuesday that the US may consider easing sanctions on Iran and other nations to help fight the coronavirus epidemic.
But Mr Pompeo gave no concrete sign that it planned to do so.
The comments reflected a shift in tone by the State Department, which has come under criticism for its hard line toward sanctions relief even after a call by UN Secretary General Antonio Guterres to ease economic penalties.
Mr Pompeo said humanitarian and medical supplies were exempt from sanctions Washington reimposed on Tehran after US Donald Trump abandoned Iran’s 2015 deal with world powers to limit its nuclear program.
But broader US sanctions deter many companis from humanitarian trade with Iran, one of the nations hardest hit by the coronavirus epidemic.
Asked if there might be a point at which the US might re-evaluate its stance on easing sanctions, Mr Pompeo said: “We evaluate all of our policies constantly, so the answer is ... of course.”
On March 20, he said US sanctions did not apply to medical and other humanitarian goods.
The Trump administration is using “maximum pressure” to try to force Tehran to curb its nuclear, missile and regional activities.
Iran’s Foreign Minister, Javad Zarif, has accused the US of engaging in “medical terror".
Mr Pompeo’s spokeswoman, Morgan Ortagus, on Monday copied Mr Zarif's tweet, and said: “Stop lying. It’s not the sanctions. It’s the regime.”
A UN human rights expert on Tuesday called for lifting international sanctions against countries including Iran, North Korea and Venezuela to ensure food supplies reached hungry people during the coronavirus pandemic.
Mr Pompeo has been sharply criticised for the administration’s stance on Iran sanctions.
In the past month, the US has repeatedly tightened sanctions on Iran, making it harder for it to sell oil abroad.
On Sunday, The Washington Post columnist Jackson Diehl published a piece under the headline: "Mr Pompeo's pandemic performance ensures his place among the worst secretaries of state ever."
“Even close US allies, such as Britain, are calling on the Trump administration to ease sanctions that are inhibiting shipment of medical supplies and humanitarian aid to Iran’s 80 million people,” Diehl wrote.
“Yet Mr Pompeo appears to view the epidemic as a handy means to compound ‘maximum pressure.’ To what end?”