LONDON —

Queen Elizabeth II marked the 20th anniversary of the Sept. 11 attacks by offering her sympathies to the victims, survivors and families affected by the atrocity.

In a message to U.S. President Joe Biden, the British monarch remembered the "terrible attacks" on New York and Washington, D.C.

"My thoughts and prayers — and those of my family and the entire nation — remain with the victims, survivors and families affected, as well as the first responders and rescue workers called to duty,'' she said.

"My visit to the site of the World Trade Center in 2010 is held fast in my memory. It reminds me that as we honor those from many nations, faiths and backgrounds who lost their lives, we also pay tribute to the resilience and determination of the communities who joined together to rebuild.''

The ties between the two nations were marked with a special Changing of the Guard ceremony at Windsor Castle in which "The Star-Spangled Banner" was played. Hundreds gathered inside and outside the walls of the castle to watch.

Watch video above to see the performance of "The Star-Spangled Banner"

The U.S. national anthem had also been played at Buckingham Palace 20 years ago on Sept. 12, 2001, a mark of solidarity with the United States.

U.S. Ambassador Philip Reeker thanked the queen for the gesture.

"Speaking for the United States, we have no closer ally and no closer friend, in good times and in bad times, and we are very much reminded of that today ... through the enduring relationship between our two countries," he said.

Prime Minister Boris Johnson has also remembered the attacks, issuing a statement ahead of the anniversary saying that the terrorists had failed to "shake our belief in freedom and democracy."

"They failed to drive our nations apart, or cause us to abandon our values, or to live in permanent fear."

Sixty-seven British nationals were among the almost 3,000 people killed when hijacked planes crashed into New York's World Trade Center, the Pentagon in Washington and a field in Pennsylvania.

To mark the 20th anniversary of the 9/11 attacks, Secretary of State Antony J. Blinken joined the Department of State in honoring the lives and memories of those we lost on Sept. 11, 2001.

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Attorney General Merrick Garland, along with the deputy attorney general, associate attorney general, and other Department of Justice officials, also spoke at the event.

Saturday marks the 20th anniversary when the lives of nearly 3,000 people were taken when terrorists of Osama bin Laden's al-Qaida terror network crashed airplanes into the World Trade Center in New York City, the Pentagon, and a field outside Shanksville, Pennsylvania.

In August, families of the victims asked President Joe Biden not to attend any memorial events unless he agreed to declassify evidence that they believe will show a connection between Saudi Arabia and the attacks.

Last week, an executive order was signed by Biden that directed the Justice Department and other agencies to oversee that documents undergo a “declassification review” about the FBI’s investigations into the attacks on Sept. 11, 2001.

The White House says the executive order requires Garland to release the declassified documents publicly over the next six months.

According to the Associated Press, publicly-released documents have detailed numerous Saudi entanglements but have not proved government complicity.

Fifteen of the 19 hijackers were from Saudi Arabia. However, the Saudi government has routinely denied any connection to the attacks.

A special report released Tuesday by the Justice Department said they believe that more people have died of 9/11-related illnesses than those killed on September 11, 2001.

The report was revealed through the 9/11 Victim Compensation Fund, a fund set up in the wake of the 2001 terrorist attacks for survivors and victims' families.

According to the report, more than 19,000 people filed a claim listing cancer as one of their eligible conditions, which makes up 48% of the claims filed.

"It is also sobering to see that more people are now believed to have died of 9/11-related illnesses than were lost on September 11, 2001," the report stated.

"As I reflect on the 20 years that have passed since September 11th, 2001, we at the World Trade Center (WTC) Health Program mourn for those lost in the attacks and affirm our commitment to those living with 9/11-related health conditions," Dr. John Howard, Director, National Institute for Occupational Safety and Health (NIOSH) Administrator, World Trade Center Health Program, said in the report.

The DOJ said more than 40,000 people had received nearly $9 billion from the VCF.

According to the Associated Press, nearly 3,000 people died on September 11, 2001, when terrorists of Osama bin Laden's al-Qaida terror network crashed airplanes into the World Trade Center in New York City, the Pentagon, and a field outside Shanksville, Pennsylvania.

The report comes just four days from the 20th anniversary.