ISLAMABAD — Pakistan on Monday publicly acknowledged for the first time it had successfully tested a submarine-launched cruise missile.

The date of the test is unclear, and the trial may have been carried out beforehand. Nevertheless, according to a statement by Inter-Services Public Relations, the military's media branch, the test of the 450-kilometer range Babur 3 was carried out "from an undisclosed location in the Indian Ocean" from "an underwater, mobile platform".

The latter implies the test was carried out from one of Pakistan's Agosta-70 or Agosta-90B submarines.

Babur 3 was stated to be a sub-launched variant of the land-based Babur 2, which was tested in December 2016 and features improved avionics and accuracy. Babur 3 features "underwater controlled propulsion and advanced guidance and navigation features, duly augmented by Global Navigation, Terrain and Scene Matching Systems."

It was also claimed to have sea-skimming and terrain-hugging flight characteristics to evade radar detection and interception — especially with regard to future regional missile defense capabilities, a veiled reference to India’s efforts in missile technology.

A further such reference to India was made in stating that the successful development of a second-strike capability was a "manifestation of the strategy of measured response to nuclear strategies and postures being adopted in Pakistan’s neighborhood."

Development of Babur 3 was also hailed as "a step towards [Pakistan] reinforcing policy of credible minimum deterrence."

Mansoor Ahmed, a postdoctoral research fellow at Harvard University's Belfer Center for Science and International Affairs and an expert on Pakistan’s nuclear program and delivery systems, said Babur 3 is a "significant milestone" in Pakistan’s effort to complete its nuclear triad.

"It has proven the speculation that Pakistan will not follow India’s pathway to a naval leg of the triad via nuclear submarines but opt for a more cost-effective solution tailored to its own strategic calculus and capabilities," he said.

Combined with the very low frequency communication facility unveiled last year, Ahmed believes Pakistan’s Naval Strategic Force Command can now deploy nuclear-armed cruise missiles on its conventional submarines to ensure a credible second-strike capability.

This is likely to be fully utilized onboard the forthcoming air-independent propulsion-equipped Hangor-class submarines designed by and co-produced with China.

Ahmed further highlighted two points: that the Babur 3 can carry any type of warhead, courtesy of Pakistan’s plutonium production program, which has enabled production of miniaturized nuclear devices for its range of missiles from Babur to the Shaheen III ballistic missile that covers all of Indian territory; and that Pakistan’s sea-based deterrent "is also likely to rely on [China’s] Beidou navigation system for precision targeting.