Chinese President Xi Jinping said Wednesday that China supports an open world economy and pledged further liberalization of its market to foreign investors — even as he touted the benefits of a socialist system at opening of the 19th Communist Party Congress.

In a three-and-a-half hour speech both retrospective and forward-looking, Xi discussed China’s progress and signaled how China sees its national development and international role in the next five years.

Of particular interest to investors will be how the world’s second-largest economy will move forward as authorities attempt to clean up the fallout from three decades of breakneck growth.

In his speech, Xi said China will push ahead with market-oriented reforms of its foreign exchange rate as well as its financial system, letting the market play a decisive role in the allocation of resources.

The government will “clean up rules and practices that hinder a unified market and fair competition, support development of private firms and stimulate vitality of all types of market entities,” Xi said, while pledging to further open China’s services sector to foreign investors.

“China’s open door will not be closed — it will be only be opened wider,” he said.

Even as Xi expressed support for market reform and private firms, he also called for stronger, bigger state firms.

The government will “promote strengthening, improvement and expansion of state capital, (and) effectively prevent loss of state assets, deepen reform of state-owned enterprises, development a mixed-ownership economy and cultivate globally competitive world-class firms,” Xi said.

The once-every-five-years Communist Party Congress, which started Wednesday, is an exercise in the election of leadership ranks in China that will culminate in the membership set-up of the Politburo Standing Committee. That top echelon of power will be announced next Wednesday, and analysts are predicting that Xi will consolidate his power and extend his term.

Over 2,000 pre-screened Chinese Communist Party members — including at least one member from the estranged territory of Taiwan — are in attendance.

Some are hoping that a more powerful Xi will be able to push through structural and economic reforms more thoroughly than he did during his first five years.

During his Wednesday address, Xi also broached the political hot potato of runaway real estate prices in the country.

Property “is for living in, not for speculating in,” Xi said to applause, an indication that the Chinese government will continue to manage the real estate market closely.

Xi’s call for more open market conditions are a welcomed signal for investors — although China is still a relatively closed market with foreign ownership of equities and bonds under 2 percent — said Ben Luk, State Street Global Markets’ global macro strategist.

Luk advised caution, as there are still many governance issues to be solved.

During his speech, Xi also signaled China’s ambitions as he said the Communist Party will develop China into a “great modern socialist country” by the middle of the 21st Century.

Touting the successes of socialism and of the Chinese Communist Party, Xi also rejected the copying of any foreign political system.

Xi’s speech followed a commentary in state news agency Xinhua on Tuesday that championed an “enlightened Chinese democracy” amid “crises and chaos” in Western liberal democracies.

“Under the leadership of a sober-minded, forward-looking [Communist Party of China], Chinese-style democracy has never been healthier and China has absolutely no need to import the failing party political systems of other countries,” it said in a commentary.

Although China’s influence is growing, it will not be a threat to any country, Xi said, pledging peaceful development on the international stage. China, he claimed, will not engage in hegemony.

Even so, Xi affirmed China’s sovereignty over the territory of Taiwan, stressing the principle of peaceful reunification. He also affirmed and touted the success of the “One Country, Two Systems” in the Special Administrative Regions of Hong Kong and Macao.

—Reuters contributed to this article.