Washington (Agencies) US Sen Carl Levin signalled to leaders in Pakistan Friday that the United States had a right to attack insurgents operating from that country if they posed a threat to American forces. The chairman of the Senate Armed Services Committee said in his remarks before the Council on Foreign Relations that Pakistan should be warned that the US will cut ties with Islamabad if it continues to support an extremist group linked to attacks on US troops. If Pakistan will not take on the threat posed by the Haqqanis and other extremist groups based in Pakistan who attack our forces in Afghanistan, then we should be prepared to take steps to defend our troops, he said. Levin said that based on international law, the US has a right to defend its troops by responding to attacks that originate from groups hiding in safe havens in Pakistan. We have the right to target not only forces and artillery attacking our forces in Afghanistan from across the border in Pakistan, but to target the people controlling those forces as well, he said, according to the text of his prepared remarks. Quoting Defense Secretary Leon Panetta, Levin added: The message [the Pakistanis] need to know is: were going to do everything we can to defend our forces. Earlier in his speech on Friday, the senator called the safe havens in Pakistan that harbour insurgents the greatest threat to security in Afghanistan, and accused the Pakistani government of offering the same excuses on why its military hasnt taken more initiative to eliminate such safe havens. At the least, Pakistan needs to condemn the attacks of the Haqqanis in Afghanistan, and Pakistani officials need to end their denials of plain truth, the senator added.