The US said Friday Iran has no right to respond to diplomacy "with military force", a day after Tehran shot down a US reconnaissance drone over the Strait of Hormuz.
"Our diplomacy does not give Iran the right to respond with military force," Brian Hook, the US special representative on Iran, told reporters in Saudi Arabia.
"Iran needs to meet diplomacy with diplomacy, not military force."
The downing of the drone -- which Washington insists was over international waters but Tehran says was within its airspace -- has seen tensions between the two countries spike further after a series of attacks on tankers the US and its staunch ally, Saudi Arabia, have blamed on Iran.
Tehran denies having been behind the attacks but has frequently threatened in the past to block the vital sea lanes into and out of the Gulf.
"Iran is responsible for escalating tensions in the region. They continue to reject diplomatic overtures to deescalate tensions," Hook said.
The US diplomat was in Saudi Arabia, where he met deputy defence minister Prince Khaled bin Salman on Friday morning.
The two discussed efforts to counter Iranian actions, Salman said on Twitter.
"We affirmed the kingdom's support for the United States' maximum pressure campaign on Iran, which came as a result of continuing Iranian hostility and terrorism, and discussed latest Iranian attacks on the kingdom," he said.
US President Donald Trump, who has repeatedly said he does not want war, offered mixed messages over the drone, warning that Iran "made a very big mistake" -- but also suggesting a "loose and stupid" Iranian general accidentally shot it down.
Tensions between Tehran and Washington have grown sharply since May last year when Trump unilaterally abandoned a landmark 2015 nuclear deal between major powers and Iran, and reimposed sweeping sanctions.
The US has since bolstered its military presence in the Middle East and blacklisted Iran's Revolutionary Guards as a terrorist organisation.
Trump has said he remains open to negotiations with Iran, but its supreme leader Ayatollah Ali Khamenei last week categorically ruled out talks with Trump after his abandonment of the nuclear deal.
Iran "has no trust in America and will not in any way repeat the bitter experience of the previous negotiations with America," Khamenei said.