WASHINGTON - The US Chairman of the Joint Chiefs of Staff Mike Mullen told Army Chief General Ashfaq Parvez Kayani he was deeply concerned about the attacks being staged by operatives loyal to the Haqqani network that operates on both the Pakistan and Afghan side of the border. In a two-hour meeting Friday night in Seville, Spain, Admiral Michael Mullen conveyed to Gen Ashfaq Kayani his deep concerns about the increasing - and increasingly brazen - activities of the Haqqani network and restated his strong desire to see the Pakistan military take action against them and their safe havens in North Waziristan, Mullen spokesman Captain John Kirby said in a statement e-mailed to newsmen. Mulllen believes that 'elements of ISI 'directly support the Haqqani network, Kirby said. US officials claim that the Haqqanis are behind some of the most high profile attacks in Afghanistan, including the attacks earlier this week against the US embassy and NATO military headquarters in Kabul. The one-on-one meeting with Gen Kayani was Mullens last as the US top military officer is retiring at the end of this month. They agreed that the relationship between our two countries remained vital to the region and that both sides had taken positive steps to improve that relationship over the past few months. They also discussed the state of military-to-military cooperation and pledged to continue to find ways to make it better, Kirby said. Both men were in Spain to attend a high level NATO military meeting. Agencies add: In response to the US demand for cracking down against Haqqani network, Kayani said a decision to launch an operation against militants in North Waziristan would be taken by the Pakistan government itself. It was the first meeting between the pair since the May 2 nighttime military raid in which US Navy Seals, without first notifying Islamabad, killed the Qaeda leader in the compound in Abbottabad where he had been hiding. As relations worsened in the aftermath of the raid, Washington announced that it could cut some of the $2.7 billion in military aid it sends to Pakistan. Islamabad, for its part, ordered as many as 200 US military trainers out of the country in the aftermath of the operation. US Defense Secretary Leon Panetta has expressed frustration that Islamabad has so far failed to crack down on Haqqani network militants that Washington suspects attacked the US embassy and NATO headquarters in Kabul on September 13-14. The raid was launched by militants firing rocket-propelled grenades at the heavily fortified embassy. At least a half dozen rocket-propelled grenades landed inside the compound, killing 15 people dead. US ambassador to Islamabad Cameron Munter said Saturday that there was evidence linking the Pakistani government with the Taliban-allied Haqqani network of militants blamed for the attack. There is evidence linking the Haqqani network to the Pakistan government. This is something that must stop, Munter told state-run Radio Pakistan. Citing unnamed Afghan officials, The Wall Street Journal reported Saturday that mobile phones found on the slain attackers after the raid indicate they were in contact with people from outside Afghanistan. The possibility that Inter-Services Intelligence agency might have been involved in the raid was considered within hours of the attack when President Barack Obamas National Security Council met Wednesday to discuss it, The Journal said. According to the paper, a senior US defense official said there was currently no actionable intelligence linking Pakistans spy service to the attack. But were looking for it closely, the official was quoted in the report as saying.