WASHINGTON: In a blunt message to Pakistan, the US has said that continued existence of terror safe havens in the country and its inability to take action against them affects their bilateral ties including security assistance."The US continues to be clear with Pakistan about steps it should take to improve the security environment and deny safe haven to terrorist and extremist groups," the Pentagon said in its six-monthly report on Afghanistan sent to the Congress yesterday."These conversations continue to affect not only US dialogue with Pakistan on security and stability in Afghanistan but also during discussion of other issues in the US-Pakistan bilateral relationship such as security assistance," the Pentagon said.US Defence Secretary Ashton Carter has not given a certification that Pakistan has taken action against the Haqqani network. As a result, the Pentagon has withheld $300 million in Coalition Support Fund to Pakistan for the current fiscal year ending September 30.The Pentagon, in a strong message to Pakistan, said the Afghanistan-Pakistan border region remained a sanctuary for various terror groups."These include the Taliban , al-Qaeda, AQIS, the Haqqani Network, Lashkar-e Taiba, Tehrik-e-Taliban Pakistan, IS-Khorasan Province and the Islamic Movement of Uzbekistan. This sanctuary and these groups remain a security challenge for both countries and pose a threat to regional stability and security," said the report running into more than 100 pages."In particular, security in Kunar Province deteriorated over the previous few months due to a series of recent attacks and limited Afghan National Defence and Security Forces (ANDSF) presence along the province's 160 mile-long border with Pakistan," the Pentagon said.According to the report, although al-Qaeda's core leadership in the Afghanistan-Pakistan border region has been degraded, elements continue to seek safe haven on both sides of the border to regenerate and conduct attack planning.The continued development of an al-Qaeda affiliate in the region -- al-Qaeda in the Indian Subcontinent (AQIS) -- highlights the dynamic nature of the terrorist and militant landscape in the region, posing risks to the mission and to US interests, it said."Pakistan must play a role in reducing the threat from terrorist and militant groups in the region," it said.Consistent mid-level military-to-military dialogue between Afghanistan and Pakistan on specific issues, such as the shared threat from IS-Khorasan Province, and occasional discussions at higher levels of the military and government early in the reporting period were encouraging, the report said."However, sustained Pakistani efforts to pressure the Haqqani Network and the Taliban and to disrupt active threat streams are necessary to help decrease violence in the region, to reduce the threat posed by these groups and to achieve lasting progress on counter-terrorism issues," it said.