Iran's Ayatollah Ali Khamenei has said the United States hit Tehran's nuclear sites but achieved 'nothing significant', as he vowed his country would 'never surrender' to its enemies.

Khamenei condemned what he called Donald Trump's 'showmanship' and claimed that the US President 'exaggerated' the impact of the strikes on three nuclear sites 'because he needed to.'

'Anyone who heard [Trump's] remarks could tell there was a different reality behind his words - they could do nothing,' the 86-year-old Iranian leader said.

The supreme leader also declared victory over Israel, despite scores of top officials and nuclear scientists being assassinated by Iran's arch enemy over the course of the 12-day conflict.

Both Iran and Israel had already claimed they won the short-lived confrontation, the deadliest and most destructive in their shared history, with Israeli Prime Minister Benjamin Netanyahu hailing on it a 'historic victory' for Israel.