The suspected mastermind of the September 11, 2001, attacks on New York and Washington has claimed that he planned and financed follow-up suicide missions on Big Ben, Heathrow airport and Canary Wharf, the Pentagon revealed yesterday.

Khalid Sheikh Mohammed, who confessed to orchestrating the 9/11 atrocities during a US military tribunal, according to a transcript released on Wednesday night, also admitted murdering the American journalist Daniel Pearl in Pakistan in 2002, according to additional testimony released yesterday.

“I decapitated with my blessed right hand the head of the American Jew, Daniel Pearl, in the city of Karachi, Pakistan,” Mohammed is quoted as saying during the secret military hearing held last Friday at Guantanamo Bay. The section on Pearl, who disappeared in Karachi in 2002, was held back for 24 hours to allow time for his family to be notified, the Pentagon said.

During an hour of rambling testimony, Mohammed, 41, the most senior al-Qaeda figure captured since September 11, claimed responsibility for the planning or execution of more than 30 terror attacks world-wide — including assassination plots to kill Bill Clinton and Jimmy Carter.

The secret tribunals at Guantanamo Bay have for years drawn fire from rights organisations across the world and from Democrats in Washington. But Democrats appeared reluctant to condemn Mohammed’s case. Bemoaning lack of due process for the greatest self-confessed criminal in US history would reinforce criticisms from Republicans that Democrats are “soft” on terrorists.

In addition to claiming responsibility for 9/11 “from A to Z”, Mohammed laid claim to a panoply of global terror attacks and plots, including spectacular plans to wreak carnage at famous British landmarks.

“I was responsible for planning, surveying and financing for the operation to destroy Heathrow airport, the Canary Wharf building and Big Ben on British soil,” he said in a two-page confession read out in his presence. The Pentagon released the transcript in an apparent effort to bolster the Bush Administration’s claim that Mohammed and other detainees were so dangerous that their continued incarceration without charge or access to full legal representation was justified, as was their ambiguous classification as “enemy combatants”.

But according to the transcript, Mohammed also alleged that he had been tortured by CIA officials after his capture in Pakistan in March 2003. He was held by the CIA in secret prisons until being moved to Guantanamo Bay with 13 other “high-value” suspects in September.

The tribunal president told Mohammed that he had received a statement “regarding certain treatment that you claim to have received” before arriving at Guantanamo Bay.

Mohammed replied: “CIA peoples. Yes. At the beginning when they transferred me . . .” The rest of his reply is edited from the transcript. The tribunal president said later: “You claim torture.” The torture allegation, and the tribunal being closed to public view, brought renewed calls for the Bush Administration to try terror suspects in public and fresh concerns about alleged use of torture by US officials.

“There’s a sort of cloud hanging over the whole Khalid Sheikh Mohammed issue,” Jack Cloonan, a former FBI counter-terrorism agent, said. “I would like to have thought that he might be sent back to the United States to stand trial, where he could have been confronted with the evidence, for all of us to see exactly what it is and who he is.” The White House refused to comment.

During the tribunal, which will determine whether Mohammed has been rightly classified an enemy combatant, he said that his confession had not been obtained under duress. When Mohammed is eventually tried, he will face the death penalty.

There was scepticism about the enormous range of plots for which Mohammed claimed responsibility, although there is little doubt among intelligence officials that he masterminded the September 11 attacks. Other evidence produced at the tribunal included a computer hard drive containing letters from Osama bin Laden, the hijackers’ codenames and a list of pilot licence fees for the lead hijacker, Mohammad Atta.

Mohammed, who described himself as bin Laden’s opera-tional chief for “all foreign operations around the world”, also claimed to have been “responsible” for the 1993 attack on the World Trade Centre, the financing and training of Richard Reid, the failed British shoe bomber, and the bombing of a nightclub in Bali, Indonesia, in 2002. The confession said that Mohammed had plotted a second wave of attacks with hijacked airliners after the strikes on September 11, 2001.

The targets were to have been the Library Tower, Los Angeles; the Sears Tower, Chicago; the Plaza Bank, Washington State; and the Empire State Building, New York.

In 2005 the US 9/11 Commission noted that Mohammed was known for his extravagant ambitions and fondness for the spotlight. It described his vision as “theatre, a spectacle of destruction with KSM as the self-cast star, the super-terrorist”. Mohammed expressed regret at the death toll of 9/11. “I’m not happy that 3,000 had been killed in America. I feel sorry even. I don’t like to kill children and the kids.”

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