'We'll go after border militants'
US defence secretary Leon Panetta has warned Pakistan that America will not allow attacks on its forces from militants based there to continue.
Pointing to the 20-hour assault against the US embassy and Nato headquarters in Kabul, Afghanistan, that finally ended on Wednesday, Mr Panetta said it was unacceptable that the Haqqani network was able to launch such deadly attacks then flee to safety across the border in Pakistan.
"The message they need to know is - we're going to do everything we can to defend our forces," he told reporters travelling with him to San Francisco, California, for meetings with Australian officials.
He refused to say whether the US planned to take any new military action, but there has been an escalating campaign of drone strikes into Pakistan's border regions. The Haqqanis are a deadly terror group based in Pakistan's lawless border area.
"Time and again we've urged the Pakistanis to exercise their influence over these kinds of attacks from the Haqqanis and we have made very little progress in that area," Mr Panetta said. "I'm not going to talk about how we're going to respond. ... We're not going to allow these types of attacks to go on."
US officials have blamed the Haqqani network for the nearly day-long assault on the heavily guarded Afghan capital. The attack left 27 dead, including police, civilians and attackers.
Mr Panetta's remarks reflect growing US impatience over Islamabad's reluctance to go after the Haqqanis, who are connected to both the Taliban and al Qaida and present the most significant threat to Afghanistan's stability.
US officials have repeatedly pressed the Pakistanis to move against insurgent havens in the border region, including in North Waziristan.
The Haqqanis use the lawless territory to launch attacks against US and Afghan forces across the border.
US relations with Pakistan have been rocky amid complaints about the increased American drone attacks across the border. But they worsened after the US special operations forces crossed into Pakistan in May to raid the Abbottabad compound where al Qaida leader Osama bin Laden had been hiding for years. Bin Laden was killed in the raid and Pakistani officials were angry about what they considered an assault on their country's sovereignty.