The Taliban denounced Saturday US moves to blacklist the Al-Qaeda-linked Haqqani network as a terrorist organisation, saying it would have no impact on operations and was indicative of US defeat in Afghanistan.
In a statement released through micro-blogging site Twitter, it said there was "no separate entity... in Afghanistan by the name of Haqqani", adding that the network's founder and its fighters were totally loyal to Taliban supreme leader Mullah Omar.
The militia, which is leading a decade-long insurgency against NATO troops and the Afghan government, claimed previous terrorist designations against its members had no impact on operations and said "this latest announcement will also be ineffective".
US Secretary of State Hillary Clinton said Friday she would press ahead with the Haqqani blacklisting, which will make it a crime in the United States to provide the network with any material support, and freeze any of their property or interests in the US.
The United States blamed the Haqqanis for a June hotel attack just outside Kabul, the 2011 siege on the US embassy and, in 2009, the deadliest attack on the CIA in 25 years.
"The Islamic Emirate does not have any trade agreements with any American companies or individuals and neither does it have monetary funds there which could be frozen," the Taliban said.
"This cowardly act of yours in which you enter mujahideen of Islamic Emirate into your so-called black list is indicative of your complete defeat and dismay."
Earlier on Saturday, the Taliban claimed responsibility for a suicide attack outside NATO headquarters in Kabul, which Afghan police said killed six young Afghans aged 12 to 17.
The Taliban claimed responsibility for the attack, saying that the CIA had been the target and that although the bombing was a month in the planning, it was also a response to US move against the Haqqanis.
The statement said the blacklisting would strengthen its determination to fight the Americans.
Founded by Jalaluddin Haqqani, a former CIA asset also close to Pakistani intelligence, it is militarily the most capable of the Taliban factions.
Former US military chief Admiral Mike Mullen said last year the Haqqani had become a "veritable arm" of Pakistan's Inter-Services Intelligence. That triggered concern that the US could indirectly be branding Pakistan a terrorist state.
But US officials downplayed such fears, insisting Islamabad had been informed in advance, and stressing the move would not hamper any future peace talks with the Taliban.