WASHINGTON (AFP/Reuters) - The United States said Tuesday it was mulling whether to blacklist Tehreek-e-Taliban Pakistan (TTP) as a foreign terrorist organisation after it was implicated in the failed Times Square bombing. The State Department designation would freeze any US assets of the TTP, ban Americans from funding or assisting the group and bar its members from entering the United States. We are considering the question of designating the Pakistani Taliban, State Department spokesman Philip Crowley told reporters. There is an intentionally deliberate process that we go through. And any group that is to be designated must meet very specific legal criteria, he said. It has come into sharp relief in light of the (failed) Times Square bombing and this is something that we are actively considering, Crowley said. He added that the investigation of the plot might shed light on whether to blacklist the Taliban. Crowley said there was a lengthy legal process before a group could be designated a foreign terrorist organisation and he did not know when a decision would be made. We have been focused on this group for some time and, without being specific, we have been working with our Pakistani counterparts and we have taken appropriate action to diminish the capabilities of this group and others in the region, Crowley said, referring to military action to target TTP leaders. A group of US senators, meanwhile, called for the TTP to be banned as a foreign terrorist organisation after officials said it was involved in the failed Times Square bombing. The designation would freeze any US assets of the TTP, ban Americans from funding or assisting the group and bar its members from entering the US. This group poses an existential threat to the safety of not only our soldiers fighting abroad but also Americans here at home, Senator Chuck Schumer, a Democrat of New York, told a news conference. Its time we confronted them with every tool at our disposal, Schumer said. Schumer, joined by four fellow senators of President Barack Obamas Democratic Party, wrote a letter to Secretary of State Hillary Clinton urging her to blacklist the TTP. The administration has hesitated in part out of consideration for relations with Pakistan, where anti-Americanism runs rife and whose government is keen to be seen as fighting the Taliban on its own terms. Schumer said he accepted the need not to blacklist Afghanistans Taliban so as not to jeopardise Western-backed efforts to reintegrate guerrillas - a key step in Obamas plan to start pulling US troops from the country. Schumer said that the Afghan Taliban - remnants of a hardline regime that sheltered Al-Qaeda before the September 11, 2001 attacks - by itself did not appear to be active abroad. The Pakistani Taliban is a different story, Schumer said. With this attack on our homeland, theyve declared war on the citizens of the US. We must respond appropriately, he said. Faisal Shahzad, 30, a naturalised US citizen born in Pakistan, was arrested two days after authorities say he parked a sport utility vehicle packed with a bomb in New Yorks busy Times Square on May 1.