Chinese President Xi Jinping issued a tough line on national sovereignty yesterday amid multiple territorial disputes with his country's neighbors, saying China will never permit the loss of "any piece" of its land to outsiders.

Xi's declaration came during a nearly one-hour speech in Beijing marking the 90th anniversary of the founding of the People's Liberation Army, which has formed a key pillar of support for the ruling Communist Party since 1927 and is the world's largest standing military, with 2.3 million members.

"The Chinese people treasure peace and we absolutely do not engage in invasion and expansion. However, we have the confidence to conquer all forms of invasion," Xi told government leaders and current and retired PLA members gathered at the hulking Great Hall of the People, the seat of the legislature that sits beside Tiananmen Square.

"We absolutely will not permit any person, any organization, any political party — at any time, in any form — to separate any piece of Chinese territory from China," Xi said to applause. "No one should expect us to swallow the bitter fruit of damage to our sovereignty, security and development interests."

Xi made no reference to any specific conflicts or disputes during his address, which focused largely on the PLA's growth from a scrappy guerrilla force fighting Chiang Kai-shek's Nationalists and Japanese invaders into one of the world's most powerful, if largely untested, militaries.

However, China is currently engaged in a weeks-long border standoff with Indian forces near the countries' disputed border high in the Himalayas, with Chinese spokesmen demanding that Indian troops withdraw to avoid a clash potentially worse than the brief but bloody war the two fought in the region in 1962.

China has also long been embroiled in a contest with Japan over East China Sea islands, as well as with five other governments over competing claims to territory in the strategically vital South China Sea. Beijing also threatens to use force to conquer Taiwan if peaceful enticements prove insufficient. China considers the self-governing democratic island Chinese territory.

Alongside its blue-water navy, China is building its first overseas military base in the Horn of Africa nation of Djibouti, and Chinese ships held drills last month with Russia's navy in the Baltic Sea, more than 10,000 kilometers (6,000 miles) from their home ports.