The Pentagon has notified the US Congress of a proposed sale of anti-ship missiles to Pakistan, including 40 air-launched and 20 ground-launched Harpoon Block II missiles and associated equipment valued at about $ 180
million.

The proposed sale would also include 300 Sidewinder missiles, a release said on Friday.

The US had on March 25 cleared the supply of about two dozen nuclear-capable F-16 fighter planes to Pakistan and in an apparent balancing exercise paved the way for sale of the same aircraft and offered civilian nuclear energy cooperation with India.

Pakistan intends to use the purchase to upgrade and modernise its existing Harpoon missile capability, it said.

"The modernisation will enhance Pakistan's legitimate self-defence capability," the Pentagon told Congress, which has 30 days to move to block any such arms sale.

"The proposed sale will contribute to the foreign policy and national security of the US by helping to improve the security of a friendly country that continues to be a key ally in the global war on terrorism," it said, adding the proposed
sales will not affect the basic military balance in the region.