WASHINGTON - In a distinct change of tone, the White House said Friday that the United States was safer because of the cooperation it received from Pakistan in combating terrorism with the world marking a decade since the deadliest attack on US soil, and the tragedy seared into Americas collective memory, honouring those lost in the disaster amid beefed up police presence at checkpoints, subway systems and airports in New York and Washington on the eve of the anniversary. It (US-Pakistan) is an important relationship and it is complicated as I have said numerous times from the podium, but America and Americans are safer because of the cooperation we have been able to achieve with Pakistan, President Barack Obamas press secretary Jay Carney said on the eve of the 10th anniversary terrorist attacks. Observers noted that Carneys praise of Pakistan came amid tensions in Washington-Islamabad ties set off by the unilateral American raid of Abbottabad in May during which Osama bin Laden was killed. Also noted was the fact that his statement did not contain the usual do more mantra. The White House Press Secretary, in an interaction with foreign journalists, also recognised the Pakistani sacrifices in the struggle against terrorists, since Islamabad joined the war against terrorism. It is important to remember that Pakistanis and Pakistan have been victims of Al-Qaeda, victims of all kinds of extremist terrorism, he noted as officials and experts in Pakistan weighed in on the heavy price Pakistan has paid in terms of human lives and economic losses in the continuing anti-terror fight and retaliatory bombings originating from the Pak-Afghan border. The Obama Administration continues to pursue a relationship of cooperation as the two countries continue to go after Al-Qaeda, Carney said, days after Islamabad captured a top Qaeda operative Younis al Maruitani. Earlier in the day, Secretary of State Hillary Clinton said while the US has significantly weakened Qaedas core leadership in Afghanistan and Pakistan, they can still conduct regional and international attacks and inspire others to do so. The threat has become more geographically diverse, with much of al Qaedas activity devolving to its affiliates around the world. I have long described al Qaeda as a syndicate of terror, not a monolith, and this is becoming truer every day, she said. For example, Qaeda in the Arabian Peninsula is reaching far beyond its base in Yemen and seeking to carry out attacks like its attempts to bring down cargo and passenger planes bound for the United States, Hillary said. Other extremist groups in the border region of Afghanistan and Pakistan not only continue to protect Qaedas remaining leadership; they are plotting attacks like the failed Times Square bombing. And from Somalia, Al-Shabaab is looking to carry out more strikes like last Julys suicide bombings that killed 76 people in Uganda during the World Cup, she said. Agencies add: President Barack Obama vowed Saturday that the United States will never waver in its fight against terrorism as Americans ready for the 10th anniversary of 9/11 under the shadow of another terror threat. Relatives of victims also gathered on a field in Pennsylvania where former president George W Bush and current Vice President Joe Biden will unveil a memorial to those who died aboard hijacked United Airlines Flight 93. Even as US intelligence agencies chased down what officials said was a credible but unconfirmed threat of an Al-Qaeda attack around the September 11 commemorations, Obama assured terrorism would never win. Ten years ago, ordinary Americans showed us the true meaning of courage when they rushed up those stairwells, into those flames, into that cockpit, the president said in his radio and Internet address. We will protect the country we love and pass it safer, stronger and more prosperous to the next generation, he added. Today, America is strong and Al-Qaeda is on the path to defeat. In London, ex-British leader Tony Blair, who played a key role in responding to the 9/11 attacks, said Western powers should be praised for reducing the terrorist threat but warned leaders not to let down their guard. The specter of fresh threats hung over Americans as they readied to mark 9/11. A US official told AFP that the general outlines of the initial report are three individuals coming into the country last month, confirming the plot had links to militants in Pakistan. US officials told US media that up to two of the operatives could be American citizens. The New York Times reported that word of the plot was passed to US intelligence agents on Wednesday by an informer based in the border region between Afghanistan and Pakistan. The informer said two US passport holders of Arab ancestry had left Afghanistan and reached the United States as recently as last week, according to the daily. But the informers report included only a vague physical description of the two men, the Times noted, with the first name for one given as Suliman, which is common in the Middle East. Former national security advisor Frances Townsend told CNN Friday that US spy networks had been alerted to a new threat after intercepting communications from a known, reliable operative in Pakistan. Its Washington or New York. A car bomb, three men. We know that one or two are US citizens, she said. The intel prompted US security agencies to scour databases and flight manifests for clues. Were looking at travel records, times, dates that people may have travelled, passenger lists, itineraries, a US counterterrorism official, speaking on condition of anonymity, told the Washington Post. Obama on Friday repeated his order for security agencies to redouble efforts to take all necessary precautions. There have been no changes to his plans to attend Sunday ceremonies at Ground Zero in New York, and Shanksville, Pennsylvania. On Saturday Bush joined current Defense Secretary Leon Panetta and Bush-era defense chief Donald Rumsfeld at a Pentagon wreath-laying ceremony to honor the Pentagon workers and airline passengers who died there. In New York, heavily armed police patrolled busy streets, trucks and cars were stopped and inspected at checkpoints and bomb-sniffing dogs scoured the subway. Similar actions were seen in Washington. The anniversary has prompted extensive reflection on how the US fared in post-9/11 security, and while a recent Gallup poll showed Americans split on whether the United States or extremists are winning the war on terror, officials were firm on US resolve to hunt down terrorists. Hundreds of people gathered in lower Manhattan on Saturday to hold hands in remembrance of the Sept 11 terrorist attacks. Families, teenagers, and others clasped hands as a bell clanged at 8:46 a.m. Saturday in Manhattan to signify the time the first of two hijacked planes crashed into the World Trade Centers North Tower. The group formed a straight line that snaked along the southern tip of Manhattan and through an exhibition of American flags, displayed to honour the dead. After a moment of silence, the group broke into applause. Some people cried. Others including strangers hugged. Meanwhile in London, Cameron told Al-Jazeera television in an interview to mark the 10th anniversary of the Qaeda attacks on the US that Britain and the United States lost some of their moral authority through some of the measures they put in place after the September 11th attacks. Some measures, such as the establishment of the Guantanamo Bay detention camp, had been a mistake, Cameron said. We can certainly see with hindsight and in some ways at the time, mistakes were made in that we lost some of our moral authority, which is vital to keep when youre trying to make your case in the world, Cameron said.