BEIJING (AFP) — China's 20th Communist Party Congress, which begins on Sunday, is expected to deliver President Xi Jinping a historic third term in control of a country his zero-Covid policy has closed off from much of the rest of the world.

Should everything go to plan, by the end of the twice-in-a-decade meeting, the 69-year-old will be reconfirmed as the party's general secretary, cementing his position as China's most powerful leader since Mao Zedong.

Security has been stepped up around Beijing's Tiananmen Square, where on Sunday almost 2,300 delegates from every province in China will gather at the imposing Great Hall of the People.

And as Xi continues to insist the country sticks to its policy of containing and eliminating the coronavirus within its borders, the Congress will take place under strict health protocols.

In a highly choreographed, mostly closed-door conclave, the participants will pick members of the party's around 200-member Central Committee, which in turn selects the 25-person Politburo and its all-powerful Standing Committee — the country's highest leadership body.

But in reality, "everything has been played out in advance, because the congress does not take place until the factions have agreed," sinologist Jean-Philippe Beja told AFP.

Critics say Xi has also eliminated any potential political rivals in recent years, especially through his long-running campaign against corruption.

Xi to stay in power

Since the 1990s, Politburo members have generally retired after two terms — but a third term for Xi would break that precedent, meaning even less than usual can be divined about the next crop of leaders.

"I think Xi will be careful in sending a clear message that no one elevated to the Politburo Standing Committee will be a successor at the 21st Congress," Steve Tsang, director of the SOAS China Institute, said.

If, as expected, Xi Jinping stays on as general secretary, he will then be confirmed as president for another term at the annual meeting of China's National People's Congress next March.

Though the 20th Party Congress will only guarantee one more five-year term, many think he will stay in power for much longer.