BEIJING -- Promising economic and political change, China's new leaders opened a meeting Saturday to debate reforms that will move the country closer to capitalism, including the first-ever guarantee of private property under communist rule.

President Hu Jintao and communist party leaders at the four-day meeting were also expected to consider a more stable legal system and measures to encourage private investment, diplomats and foreign analysts said.

The meeting coincides with final preparations for China's first manned space mission next week and reflects the party's desire to link itself to the nationalistic fervor of a history-making triumph, helping to repair a reputation battered by corruption scandals.

Details of the agenda of the plenum of the 16th Communist Party Congress weren't immediately released. But the official Xinhua News Agency said it would push ahead economic reforms that have let millions of Chinese lift themselves out of poverty.

It marks "another turning point and a new starting point in China's reform process," Xinhua said.

The meeting comes as Hu, little understood after nearly a year as party general secretary, tries to establish himself as China's leader following the 13-year rule of Jiang Zemin.

Hu, 60, has moved cautiously as he tries to consolidate power, sharing control with Jiang allies on the party's ruling nine-member Standing Committee. Jiang, 77, is still influential as chairman of the commission that runs China's military.

Though Hu has called for making government more accountable and responsive, he has yet to reveal any detailed vision.

Possible changes foreseen by outside experts in a Hu government reflect long-planned shifts in party strategy, not his personal ambition.

Hu gave his most explicit indication of possible changes in a Sept. 30 speech that called for greater "socialist democracy" and a bigger public role in government. But he didn't say how that would be carried out, and the party has given no sign that it includes true political opposition.

Instead, political changes spearheaded by Hu appear to be aimed at making the party more flexible and responsive to a society that is undergoing wrenching change.

As the plenum began Saturday, Xinhua indicated that such change already was under way. It said the 24-member ruling Politburo would present a report on its work to the lower-ranking, 356-member Central Committee -- the first time the closed, secretive elite has submitted to outside scrutiny, even by another party body.

That decision "makes clear the newest efforts of the Politburo ... to advance and foster intra-party democracy and the strengthening of the party's vitality," Xinhua said.

Party leaders who, along with Hu, took office last November also face a wide array of other problems: rural poverty, banks mired in bad loans and job losses at state industry.

Though incomes have risen sharply, the average Chinese earns only about $700 a year. Communist leaders worry that anger at poverty and official abuses could spin out of control, threatening the party's monopoly on power.

The proposed constitutional change that outsiders say would protect private property comes after a 1999 amendment that declared private business an "important component" of the economy.

Xinhua confirmed that the plenum was to consider a constitutional amendment -- though not what it was.

The report said party leaders already had decided change was needed to meet "demands arising from China's economic and social development."

The amendment could enshrine the thinking of Jiang, the former leader who invited capitalists into the party, according to earlier reports by state media.

Jiang's ideology is aimed at keeping the party relevant and entrenching its control amid a growing private economy by drawing entrepreneurs into its ranks.

Jiang, 77, gave up his post as party leader last year and retired as president in March, but he still holds influence as chairman of the commission that runs China's military.

Writing his thinking into the constitution could give Jiang a shot at one of his last ambitions -- a place in history on the level of Mao Zedong, the country's Communist founder, and Deng Xiaoping, who launched its economic reforms.