ISLAMABAD, Pakistan - India has embarked on a series of crucial weapons-systems tests that will result in the first deployment by air, sea and land of nuclear weapons by rival powers in Asia, in 2016.

The creation of what military planners call a nuclear theater in South Asia would pit India against neighboring foes China and Pakistan, nations with which India has fought a total of seven wars since 1947. The region has a population of 2.8 billion, nearly 39 percent of the world's people, according to 2014 estimates by the U.S. Census Bureau.

India fought a 1962 war with China and has had six conflicts with Pakistan since attaining independence in 1947, mostly territorial disputes left unresolved by departing British colonial rulers.

The strategic game change in South Asia comes as India perfects its ability to hit targets anywhere in China with nuclear-tipped intercontinental ballistic missiles and establishes an ability to launch nuclear missiles from submarines.

The completion of India's air-, land- and sea-based nuclear weapon triumvirate would place it on rough strategic par with China, its major rival for power in South Asia and Pakistan's key ally.

"The reality of an arms race in South Asia is quite evident. For most Indian decision-makers, it is the China factor that remains the most important issue. [New] Delhi also fears a China-Pakistan axis, and so it feels the needs to be prepared for a 'two-front' war," said Harsh V. Pant, an Asia security expert and professor of international relations at King's College London, a British university.

China possesses about 250 nuclear weapons and Pakistan has up to 120, compared with India's 110, according to a report published Nov. 23 by the Council on Foreign Relations, a U.S. research organization. Only the United States and Russia possess more.

The series of strategic events in South Asia started last Tuesday with the Indian military's first successful test of the 2,500-mile-range Agni-IV, the first Indian ballistic missile capable of delivering nuclear or conventional warheads deep into Chinese territory. It's scheduled to be deployed by India's strategic forces command in late 2015.

Later in December, India's strategic weapons trailblazer, the Defense Research and Development Organization, is scheduled to test the road-mobile delivery platform of its first true intercontinental ballistic missile, the Agni-V. With a range of up to 3,400 miles, it would extend India's strategic reach to the rest of China when pressed into service in 2016.

The achievement of that key objective of India's land-based strategic weapons program would be accompanied in 2016 by the Indian navy's deployment of its first nuclear weapons-carrying submarine.

Soon to begin sea trials, the Arihant is the first of three homebuilt Indian subs that would each carry either four or 12 missiles with a 2,200-mile or 440-mile range, respectively, strongly suggesting a choice of mission between targets in China or Pakistan.

The likely deployment of India's first nuclear-armed submarine prompted China to dispatch its submarines on a tour of the Indian Ocean for the first time this year. Provocatively, the two conventionally armed submarines called at a Chinese-operated port in Sri Lanka, off the southern tip of India.