Backing British Premier David Cameron's call to Pakistan to stop exporting terror, the US says more needs to done by Islamabad in fighting terrorism. The Obama Administration also said it has been made very clear to Pakistan that it must stay on the offensive in combating extremist elements within its borders and in the tribal areas on the Afghan border.State Department spokesman P J told reporters at his daily news conference yesterday that our joint concern is to eliminate the existing safe havens in the region and to prevent the emergence of new safe havens. When asked about the comment made by Cameron during his visit to India, Mr. Crowley said US does not want to see the export of terror by any country. He said that Pakistan has taken the most aggressive and strongest ever action against terrorists in the country and US wants that to continue.