NEW YORK - Pakistan has more terrorists per square mile than any other country in the world, making it the most dangerous place on earth, claims a former CIA officer. Pakistan is our most important partner in the war against al Qaeda and the most difficult partner in the war against al Qaeda. Bruce Riedel, author of 'Deadly Embrace: Pakistan, America and the Future of Global Jihad told FOX News in an exclusive interview, adding that President Barack Obama should give Pakistan the top priority as a matter of national security. It has the fastest growing nuclear arsenal in the world and it has more terrorists per square mile than any other country in the world, Riedel, who also authored the Obama administrations AfPak strategy, said. Riedel, now a fellow at the Brookings Institution think tank, says the US must pursue a two-track approach with Pakistan, according to his book. On one hand, he supports a five-year, $1.5 billion non-military aid package sponsored by senators John Kerry and Richard Lugar that is still stalled in Congress. The money, Riedel says, will help convince the Pakistani people that the US is seeking a long-term friendship. But he also says the US should get tough with Pakistans top generals and members of its intelligence service, the ISI, if there is evidence about their support to the Taliban or al Qaeda. He suggests placing offending officers on the US terror watch list, which means their overseas assets would be frozen. Imagine a state with the fastest growing nuclear arsenal in the world, the sixth largest army, thats an active sponsorof terrorist groupsthat welcome Osama bin Laden and al Qaeda out of their hiding places into the presidential palaces in Islamabad, Riedel said. Thats the nightmare that we have to worry about. And thats the nightmare that we have to avoid at all costs. Critics of the administrations current policy suggest that the Obama team has not taken a tough enough line when it comes to the suspected ties between Pakistans military and intelligence organisations and the Taliban and other radical groups, the report said. KT McFarland, a nuclear proliferation and national security expert who worked during the Reagan era in Pentagon, said the US must be more demanding with its troublesome ally. Weve let the Pakistanis tell us what they want, and frankly they are playing both sides, said McFarland. On one hand, they are helping us in Afghanistan and with al Qaeda against the Taliban, but on the other hand they are helping the Taliban too, because they are hedging their bets, the security expert added. McFarland suggested that the US should tell the Pakistan government to get serious about searching for Osama Bin Laden, who is believed to be hiding in the mountainous eastern region of the country. I think we need to go to Pakistan and say, Look, you guys have had almost 10 years. We know that Osama Bin Laden is in Pakistan. If you want the relationship to continue, we want Osama Bin Laden, said McFarland.