The clean-up will be conducted in the context that China's economic growth will be kept within "a reasonable range", it added.
Lu Zhengwei, chief economist with Industrial Bank in Shanghai, said Xi's message was "making progress while ensuring stability". This meant Xi was ruling out any stimulus or monetary easing, Lu said.
"A three-year campaign was set to give markets stable expectations and prevent acting with "undue haste," he added.
Xie Yaxuan, a macro analyst with China Merchants Securities in Shenzhen, said Xi needed time to map out risks and deploy "measures to address them.
"Xi's downplaying [of] growth targets "does not mean growth is no longer important," Xie said.
Efforts to contain risks and debt would not be made at the price of the economy, he said.
Xi has secured an official name for his economic policy package — "Xi Jinping Economic
Thought on Socialism with Chinese Characteristics for a New Era" — and the leadership said China now has the world's largest middle-income population.
The financial sector must help China's structural reform and create a "virtuous circle" with the real economy and the housing market, the statement said. Meanwhile, the government will continue to crack down on illegal financing activities to stem risks.
Hao Hong, chief strategist of Bocom International, said Beijing had acknowledged there would be some trade-offs in terms of policy objectives.
"[The government] has paid less attention to investment starting from this year. While infrastructure construction has largely offset the decline in property investment, the contribution of consumption to GDP growth has been rising," he said.
The good, bad and ugly sides of Xi's economic work conference
On the environment, the top leadership vowed to cut pollutants over the next three years as it tries to "defend blue skies".
The meeting was intended to translate Xi's ideas about development into specific policies after the president pledged to pursue high quality, instead of fast, growth in the "new era".
The tone was set in Xi's report to the party congress in October.
The 25-member Politburo then set the agenda ahead of the conference by identifying the three key economic "battles" for 2018: tackling financial risk, curbing pollution and reducing poverty.
Iris Pang, chief Greater China economist at ING, said Beijing's push to rein in excessive credit and control debt was "a double-edged sword" that could affect economic performance.
"A slight move in the financial system — such as a bank credit control or an interbank liquidity squeeze — may affect the whole situation "and that deserves special attention from the regulators," she said.
More than 400 officials, including top economic cadres, provincial governors and executives from state-owned firms and financial institutions, attended the conference.
On Tuesday, Beijing hit back at America's "cold war mentality" after US President Donald
Trump laid out a new national security strategy in which he labelled China as a competitor.
Washington's growing hostility, along with expected Federal Reserve interest rate rises and US tax cut plans, may hurt China's trade and growth next year and create capital outflow pressure.
The communique released after the conference on Wednesday did not explicitly mention Washington, but it said China would seek to balance trade by boosting imports.
— South China Morning Post