China's main share index climbed nearly 5%
China's main share index has risen nearly 5% after a senior official said regulators would seek to promote steady development of the stock market.
The comments from Liu Xinhua, vice chairman of the China Securities Regulatory Commission (CRSC), sparked hopes of government policy support.
The Shanghai Composite Index closed up 4.8% at 2,845.02, with metal stocks leading the way up.
Shandong Gold rose 10% after gold prices hit a three-month high.
Mr Liu said the outlook for the world economy was still unclear, while China's recovery was neither stable nor balanced.
"However, the CSRC will try hard to maintain the continuous, stable and healthy development of the securities market," he said.
Separately, on Wednesday, the International Monetary Fund (IMF) said China had agreed to buy $50bn (£31bn) of its first bond issue.
The move will strengthen the IMF's lending ability as it tries to raise money to finance lending to help economies get through the global downturn.
The agreement also offers China "a safe investment instrument", the IMF said.