India and Pakistan on Saturday exchanged the list of their nuclear installations and facilities, an annual ritual of both countries that are agreement bound to share the relevant information by January 1 of every year. This list was exchanged under the Agreement on the Prohibition of Attack against Nuclear Installations and Facilities between India and Pakistan, both nuclear-weapon states, which was signed on December 31, 1988.

This was the 31st consecutive exchange of such top-secret lists between the two countries, the first one having taken place as far back as January 1, 1992.

"India and Pakistan today exchanged, through diplomatic channels simultaneously at New Delhi and Islamabad, the list of nuclear installations and facilities, covered under the Agreement on the Prohibition of Attack against Nuclear Installations and Facilities between India and Pakistan," the Ministry of External Affairs (MEA) said in a statement.

The agreement, which entered into force on January 27, 1991, provides, inter alia, that India and Pakistan inform each other of the nuclear installations and facilities to be covered under the Agreement on the first of January of every calendar year, MEA said.

Under this nuclear agreement, both countries are supposed to inform about the latitude and longitude of their nuclear installations and facilities.

The term "nuclear installation or facility" includes nuclear power and research reactors, fuel fabrication, uranium enrichment, isotopes separation and reprocessing facilities as well as any other installations with fresh or irradiated nuclear fuel and materials in any form and establishments storing significant quantities of radioactive materials.

Separately, the two sides also exchanged the lists of civilian prisoners and fishermen in their custody. This is in keeping with the provisions of the 2008 Agreement under which such lists are exchanged every year on 1st January and 1st July. Both the numbers run into hundreds as civilians, including scores of fishermen, are routinely straying across the border or into each other's territorial waters, especially while fishing in the sea, posing a humanitarian challenge for both countries' bureaucracy hidebound by layers of stiff diplomatic rules and protocols (SAM).