Former President George W. Bush has offered a candid insight into what went on in the aftermath of the attacks on September 11. 

The former commander-in-chief, 80, was speaking at his presidential library in Dallas alongside former Secretary of State Condoleezza Rice when he made the remarks.

Rice described the chaos that engulfed the executive branch in the aftermath, and how they managed to have the CIA and FBI work in unison. 

She said: 'On the day after the attack, we're sitting in the Oval Office and because the FBI and the CIA had not really been able to talk to each other because of civil liberties.

'For the first time we had to forge intelligence between them by having Bob Mueller and George Tenet come into the Oval Office every morning and show the president what they saw in the threat matrix.

According to Rice, the threat matrix compiled by the two groups was the size of a phonebook on the morning of September 12. 

Bush added: 'The sad thing is one-third of our nation has no clue what we're talking about. 

'They never witnessed this sacrifice and the courage and the dedication to serve a neighbor in need.'

Rice went on to recall raising her voice at Bush in the immediate aftermath of the attacks. 

'I did something I would do again. I raised my voice to you because you said "I'm coming back."

'And I said, "stay where you are, the United States of America is under attack. It is not safe here.'

At the time of the attacks Bush was at a school in Florida, listening as a young student read out to a class full of children. 

He recalled leaving the school, flying to a military base in Louisiana then on to another base in Omaha, Nebraska, before he then addressed the nation. 

Bush also remembered spending the night inside a bunker below the White House before taking calls from world leaders the next day. 

He added: 'I didn't want us to lose our soul. I wanted to, as we defended our freedoms, I wanted people to remember how precious they are.'

Bush is expected to attend a ceremony on Friday at Ground Zero alongside former Presidents Obama, Biden and Clinton as well as Vice President JD Vance. 

The attacks saw al-Qaida conspirators seize control of airplanes and hit New York's World Trade Center and the Pentagon near Washington.

A fourth plane was headed for Washington but crashed in Pennsylvania after crew members and passengers tried to storm the cockpit. 

Officially, the casualty count associated with the attacks is numbered at 2,996 - including 2,977 victims and 19 hijackers. 

Thousands more were injured, and New York bore the brunt of the death toll - with an estimated 1,600 victims in the North Tower and another thousand in the South.

First responders and survivors have developed illnesses due to exposure to toxins in the air, with thousands of people dying due to 9/11 related cancers and other illnesses.  

Earlier this week New York City Mayor Zohran Mamdani released over 170,000 pages of previously undisclosed records concerning the air quality after the attacks. 

The documents showed that city officials at the time knew that the air at Ground Zero was unsafe to breathe despite repeated assurances to the public.