"All regions and people of all ethnicities in Tibet will march toward a happy life in future," Xi Jinping tells a crowd in one video of his visit. "I am full of confidence as you all are. Lastly, I will not delay your dancing. Let me say this: I wish everyone a happy life and good health."

Xi Jinping pledged to bolster construction along Tibet's Himalayan frontier, as the Chinese president reaffirmed Beijing's control in his first official trip to the border region.

Xi called on ethnic Tibetans and other minority groups Friday to help defend the country in a visit timed to mark the 70th anniversary of the Communist Party's control over the area, according to the official Xinhua News Agency. The trip, which included a stop in the Chinese military hub of Nyingtri, comes as tensions simmer along the country's contested border with India, amid claims by both sides of aggressive troop movements and infrastructure building.

"His message will be especially troubling for India," said Robert Barnett, a British academic who has written about Tibet, as he posted videos showing the Chinese leader speaking to locals. Barnett said Xi's trip "suggests that he places the border struggle with India close to the very top of China's national agenda."

The People's Republic of China this year marked the 100th anniversary of its founding, as well as seven decades of control over Tibet. The push into the region in 1951 was part of a broader effort by Mao Zedong's Communists to consolidate control over territory historically claimed by China before decades of colonialism, war and internal strife.

Riots erupted in the Tibetan capital of Lhasa in 2008 over allegations of religious oppression, leaving at least a dozen dead. A spate of self-immolations by ethnic Tibetans followed a few years later.

Xi arrived in the regional capital Lhasa on Thursday accompanied by an entourage including Vice Premier Liu He, China's economic czar, and Zhang Youxia, vice chairman of the country's top military body. While Xi urged respect for Tibetan culture -- visiting a monastery and using local greetings -- he emphasized the ethnic-assimilation policies that have drawn international criticism, calling for officials to promote "ethnic harmony" and to "actively guide Tibetan Buddhism to adapt to a socialist society."

"All regions and people of all ethnicities in Tibet will march toward a happy life in future," Xi tells a crowd in one video of his visit. "I am full of confidence as you all are. Lastly, I will not delay your dancing. Let me say this: I wish everyone a happy life and good health."

"Tashi Delek," he adds, using a phrase wishing good fortune.

Both China and India have bolstered military forces along their contested frontier after the deadliest fighting in decades last year, with New Delhi redirecting at least 50,000 extra troops to the border. Earlier this month, Foreign Minister Subrahmanyam Jaishankar and his Chinese counterpart Wang Yi agreed to continue discussions over the border standoff.

"China will strengthen infrastructure construction along the border, and encourages people of various minorities to set their roots at the border, to defend the territory and build the homeland," Xi said, according to Xinhua.

China has faced criticism for its policies in Tibet, which has been subject to intense social, security and religious controls, much like its northern neighbour Xinjiang. In September last year, prominent Xinjiang researcher Adrian Zenz released a report alleging that Beijing was instituting a mass labor system in Tibet similar to the one that has ensnared Muslim Uyghurs.

Tibet Governor Qi Zhala said at the time that forced labour transfer "does not exist," maintaining the local government was focused on providing job training. In May, Wu Yingjie, the party chief in Tibet, lauded the progress Beijing has made developing the region, saying that "religion has been increasingly compatible with a socialist society."

"The timing of his visit seems designed to de-emphasize China's original promises of autonomy and freedom to Tibetans, and instead to emphasize to Tibetans that they owe everything to the Communist Party," said Barnett, the academic.

Xi's visit comes about two weeks after Tenzin Gyatso, the 14th Dalai Lama, turned 86. The choice of successor to the spiritual leader of the Tibetans, who now lives in exile in India, is shaping up to be a struggle between India and the US on one hand and China on the other.

Senior security officials in India, including in the prime minister's office, have been involved in discussions about how New Delhi can influence the choice of the next Dalai Lama, Bloomberg News reported in April. China's Foreign Ministry has said the reincarnation of the Dalai Lama is an internal affair that "allows no interference."

Tenzin Lekshay, a spokesman for the Tibet government in exile in northern India, said in a tweet late Thursday that Xi should "understand the true aspiration of Tibetan people and resume the dialogue to resolve the Sino-Tibetan conflict."