BANGALORE: India welcomed a senior Chinese delegation from Beijing for the first time at its air show on Wednesday even as the country's defence minister warned of a military build up on their border.

Air Vice Marshal Zheng Yuanlin headed a five-person Chinese group at the Aero India show in Bangalore after New Delhi extended its first invitation to China in January.

The move came after a decision last September to resume joint military exercises following the first visit of a Chinese defence minister to New Delhi in eight years.

“It is a welcome step, even though we have long pending border issues,” Defence Minister A.K. Antony told reporters. “We are trying to improve relations in all areas.”

The last Aero India in 2011 saw New Delhi snub China again along with arch-rival Pakistan amid a spike in tensions, but the Chinese ambassador in New Delhi was allowed to attend in a negotiated compromise.

Suspicion of China runs deep in the Indian military and hawkish comments from senior commanders often conflict with the political leadership, which stresses the need for a partnership between Asia's two biggest nations.

Antony said that a border management agreement signed by the countries had helped reduce tensions on the frontier between Tibet and northeastern Indian states, but he warned about a military build up.

“They are reinforcing infrastructure in a big way... The government of India is bound to modernise our armed forces. Strengthening our border by way of infrastructure by putting more assets there is our duty,” he said.

“This is not for a confrontation, but at the same time we must be ready to face any eventuality.”

He also said that New Delhi was concerned by Pakistan's decision last month to hand over the management of a strategically located deep-sea port in the Arabian Sea to China.

Pakistan transferred the Gwadar port on January 30 from a Singapore company to China, which provided most of the funding to build the facility in the province of Balochistan.

“In one sentence, it is a matter of concern for us,” Antony said.

China has been extending its influence with traditional allies of New Delhi around the Indian Ocean as well as in neighbouring Pakistan, where it is the country's main arms supplier.

India and China claim parts of each other's territory, while competing interests in the South China Sea and Indian Ocean are frequent sources of friction.

Military cooperation was called off in 2010 after a row when China refused a visa to an Indian commander stationed in the disputed region of Kashmir.

The two sides have held more than a dozen rounds of inconclusive talks to resolve their border disputes, which led to a brief but bitter war in 1962.

Much of India's huge military modernisation – it is the world's biggest arms importer, according to monitors – and its expanding long-range missile programme is seen as partly in response to China's rise.

The Indian military has traditionally seen neighbour Pakistan as its biggest foe after three wars since independence in 1947.

But as India's economic interests spread geographically, Indian leaders see the need to be able to project force further afield while also defending against any future threat from Pakistan or China.