WASHINGTON (Agencies) - US Secretary of State Hillary Clinton insisted that Pakistan and Afghanistan remain the centre of terrorist activities in the world. Contending that 'much of the planning' for terror strikes around the world was taking place in Pakistan and Afghanistan, the United States has said it wants to help the two countries to deal with the menace. The threat of terrorism is one that every nation and every group of people has to confront with, Secretary of State Hillary Clinton told a meeting of young European leaders in Brussels, while condemning the recent attack on the Sri Lankan cricket team in Lahore as 'just another senseless, violent act'. While the world has a united front against terrorism, she said it is also imperative that 'we send a message to the individuals and the communities from which they come that we will neither tolerate nor give in to terror as a tactic, and that we offer an alternative to those who are willing to pursue it'. Clinton insisted that Pakistan and Afghanistan remain the centre of terrorist activities in the world. "We are very conscious of the fact that much - not all, but much - of the planning of terrorist activity is coming from a network that is primarily based in Pakistan and Afghanistan, along the border in areas that are very difficult for either the Government of Pakistan or Afghanistan or any of our military forces to be able to reach," she said. "We are engaged in the Obama Administration in a policy review of our approach to Afghanistan-Pakistan, because we see them together. We want to help support the people of those two countries against the encroachment of terrorist networks," Clinton said on Friday, according to the transcript made available by the State Department here. Clinton said the US is working hard to prevent the acquisition of any weapon of mass destruction by a terrorist network. There is a constant vigilance on the part of law-enforcement and intelligence here in Europe, working with US and others around the world to avoid what would be a calamity, she said. "We know that the terrorist networks are determined to try to obtain the fissile materials for a true nuclear weapon. They are also equally interested in chemical or biological or radiological weapons as well," Clinton said. "Supporting governments, supporting people acting in good faith trying to deal with the terrorist threats on their own territory has to be one of the highest priorities of the EU, the United States and all of the nations represented here," she said.