Iran’s Supreme Leader Ayatollah Ali Khamenei has said Iran will “never surrender” to the United States, striking a defiant tone in his first remarks since a ceasefire with Israel took hold, according to Aljazeera.

Khamenei, 86, claimed victory after 12 days of war, culminating in an Iranian attack on the largest US military base in the Middle East, in Qatar, after the US joined the Israeli assault.

“The US President [Donald] Trump unveiled the truth and made it clear that Americans won’t be satisfied with anything less than surrender of Iran … such an event will never happen,” Khamenei said.

Khamenei’s remarks come two days after a ceasefire halted the war between Iran and Israel – the foes’ deadliest and most destructive confrontation – and mark his first public appearance since June 19.

The speech also comes amid conflicting accounts in the US over the extent of the damage inflicted by US strikes on key Iranian nuclear sites at Fordow, Natanz and Isfahan during the conflict. US President Donald Trump said the strikes “obliterated” the nuclear facilities.

But Khamenei said Trump had “exaggerated” the impact of the attacks and said the US “gained nothing from this war,” claiming the US strikes “did nothing significant” to Iran’s nuclear facilities.

“The Islamic republic won, and in retaliation dealt a severe slap to the face of America,” he said, a reference to Iran’s missile attack targeting the US airbase in Qatar, which caused no casualties.

Al Jazeera’s Resul Serdar, reporting from Tehran, said Khamenei also focused on the country’s armed forces, to offer them congratulations and counter the claims around the world and in Iran that the army “has received huge blows from the Israeli attacks”.