"Since the late 1980s and early 1990s, Pakistan has invested in both solid-motor and liquid-engine ballistic missile programs with Chinese and North Korean assistance, respectively. Pakistan's reasons for investing in both solid- and liquid-propulsion technologies remain unclear. However, analysts speculate the rival programs could be the result of intra-institutional rivalry and one-upmanship between the Pakistan Atomic Energy Commission (PAEC) and Khan Research Laboratories (KRL), which have historically feuded over control and credits for Pakistan nuclear weapons-related efforts. This rivalry may have also carried over to the development of nuclear delivery systems. Furthermore, the diversification effort could also be viewed as a proactive attempt on the part of Pakistan's military to factor in possible bottlenecks or failure along one technological front, as well as an attempt to diversify suppliers in the face of U.S. efforts to restrict the international trade in weapons of mass destruction-capable ballistic and cruise missile technologies.

Although Pakistan's current fleet of missiles is restricted to SRBMs, the National Defense Complex (NDC) and KRL are actively pursuing programs to develop medium-range ballistic missiles. Most analysts believe that the Pakistani military has achieved or is close to achieving the capability to mount nuclear warheads on its current ballistic missile fleet. Some reports even go so far as to suggest that Pakistan may be further along than India on the path to achieving nuclear operability.[3]

Pakistan underscored its commitment to strengthening its military capability against India by conducting two ballistic missile tests in quick succession in February and March 2007, even as the two subcontinental rivals continued discussions on nuclear confidence building measures and anti-terrorism initiatives. The Pakistani tests came at a time when India has also sought to strengthen its strategic capabilities vis-à-vis Pakistan, as well as narrow the gap with China through development of more capable nuclear delivery vehicles, including advanced combat aircraft and missile systems.

Since 2005, Islamabad has also carried out several tests of its Babur (Hatf VII) cruise missile, two such tests coming in March and June 2007. This subsonic nuclear capable missile, has a range of 700 km.[48] In addition, in August 2007, Pakistan tested a new cruise missile, the Ra'ad (Arabic for "Thunder"). This missile, which is air-launched, has a range of 350 kilometers.[49] Thus, along with ballistic missiles, cruise missiles are increasingly part of Pakistan's nuclear calculus. [50]"

http://www.nti.org/e_research/profiles/Pakistan/Missile/index_3066.html