Khamenei starts speakingpublished at 11:39 British Summer Time
Khamenei's speech has just begun - we'll bring you lines on what he's saying very shortly.
Summary
US Defence Secretary Pete Hegseth calls US strikes on Iranian nuclear sites at the weekend "historically successful"
Speaking at a Pentagon news conference, Hegseth cites various assessments, including from the CIA and the UN's nuclear watchdog
Hegseth also attacks the media, after a leaked intelligence report earlier this week suggested the strikes' impact may have been limited
The update comes after Iran's supreme leader said the US "failed to achieve anything significant" with the nuclear strikes
Ayatollah Ali Khamenei also claims victory over Israel - and says Iran delivered a "heavy slap" to the US by attacking a US base in Qatar
So has Iran's nuclear programme been destroyed, or merely set back? We still don't know, writes our correspondent Frank Gardner
Hegseth cites foreign Iran attack assessments, pushes back against press
Khamenei starts speakingpublished at 11:39 British Summer Time
Khamenei praises unity of Iranian peoplepublished at 11:36 British Summer Time
Ghoncheh Habibiazad
BBC PersianAyatollah Khamenei has just posted another message, this time reported by the semi-official Fars News Agency on Telegram.
"A third congratulation, congratulations on the unity of the Iranian nation," he writes.
"A nation of around 90 million stood united, with one voice, shoulder to shoulder, in support of the armed forces.
"The Iranian nation demonstrated its distinguished character and showed that, when necessary, a single voice will be heard from this nation."
Iran delivered a 'hard slap to America's face'published at 11:28 British Summer Time
We can now bring you more from Ayatollah Khamenei, who in a post on X says congratulations once more to his country, focusing this time on "our beloved Iran's victory over the American regime".
He says the US "entered a direct war because it felt that if it did not, the Zionist regime would be completely destroyed".
Khamenei goes on to suggest the US "gained no achievements from this war," adding that Iran was able to emerge "victorious" and "delivered a hard slap to America's face".
- In a later English-language message, the Ayatollah says "the Islamic Republic delivered a heavy slap to the US’s face"
Khamenei not seen for more than a weekpublished at 11:19 British Summer Time
Image source, EPAImage caption, Khamenei was last seen by the public on 18 June when he gave a televised statement
Iran's supreme leader has not been seen for over a week - he last gave a televised statement from an undisclosed location on 18 June.
Earlier today, Israeli media was heavily questioning the whereabouts of Ayatollah Ali Khamenei.
BBC Monitoring - which looks at media reports - said Israeli media have been keen to highlight prospects of regime change inside Iran and hopes that Israeli strikes on Iran could spark protests against the leadership from within Iran.
On Channel 14 News, commentators claimed Khamenei's days as leader are numbered, adding that he's in a state of "mental anguish".
What has the US bombed and what weapons were used?published at 11:11 British Summer Time
While we wait for Ayatollah Khamenei's video address to be broadcast, let's have a look at what we know about the impact of the US strikes on Iran.
Washington says the strikes have significantly set back the prospects of Iran building nuclear weapons after three of Tehran’s main nuclear facilities were hit.
The operation – nicknamed Midnight Hammer - involved 125 US military aircraft and involved the sites of Fordo, Isfahan and Natanz.
They were hit between 22:40 GMT and 23:05 GMT on Saturday (02:40-03:05 on Sunday Tehran time), the US says.
Fourteen GBU-57 Massive Ordnance Penetrators (MOPs) were dropped on the Fordo site, a nuclear enrichment facility buried deep below a mountain outside Tehran, which is vital to Iran's nuclear ambitions.
At the same time, two dozen cruise missiles were launched at the Isfahan site from a submarine – in total, 75 “precision-guided weapons” were used during the operation.
Ayatollah says Iran secured 'victory' over Israelpublished at 11:02 British Summer Time
Breaking
Image source, Getty ImagesAs we wait to bring you the top lines from Khamenei's speech, the ayatollah has just posted on X to congratulate the Iranian people for the "victory" over Israel.
"I offer my congratulations on the victory over the fallacious Zionist regime," he writes.
Iran's Ayatollah speaks for first time since ceasefire as Hegseth prepares 'major' updatepublished at 11:01 British Summer Time
Ayatollah Ali Khamenei, Iran's supreme leader, will speak within the next few minutes in a video message, marking his first message since the US announced a ceasefire between Iran and Israel.
The message comes hours before US Defence Secretary Pete Hegseth is due to hold a news conference, where he'll give an update on the impact of US strikes on Iran's nuclear facilities over the weekend.
US President Donald Trump, writing on Truth Social, says the "major" update will be delivered from the Pentagon at 08:00 EST (13:00 BST), when Hegseth will be joined by military representatives.
"The News Conference will prove both interesting and irrefutable," Trump adds.
Speaking from a Nato summit yesterday, Hegseth was emphatic that US strikes had significantly diminished Tehran's nuclear capabilities.
But earlier reports quoting US intelligence sources suggested the strikes had only set Iran's nuclear programme back by months and key components had not been destroyed.
Stick with us as we bring you the latest updates on this story.