Pakistan currently have 111 points, one ahead of India, while Australia and England have 108 points each.
Pakistan achieved the No. 1 Test ranking for the first time since the current rankings system was introduced in 2003 after it drew the series against England 2-2.
Pakistan's cause was also helped by Sri Lanka, who defeated Australia 3-0, while a wet ground in Port of Spain denied India the opportunity to defend the top spot as they won their four-Test series against the West Indies 2-0.
Pakistan currently have 111 points, one ahead of India, while Australia and England have 108 points each.
The top seven Test sides are separated by just 16 points.