BEIJING -- Chinese stocks rallied in the morning session on Friday, helped by the government's decision to invest in infrastructure construction to bolster growth.

The benchmark Shanghai Composite Index gained 4.2 percent to end the morning trading at 2,138.02, after persistently hitting a record low points during previous trading days. The Shenzhen Component Index closed at 8,790.62, up 6.06 percent.

The rally came as the National Development and Reform Commission, the country's top economic planner, earlier this week approved 25 urban rail projects worth more than 800 billion yuan ($126 billion), 13 road projects and a number of schemes for ports and waterways construction.

The move marks the government's latest effort to stabilize growth as external demand remains weak caused by a struggling US economy and the eurozone debt woes.

Investors expect positive changes and a lift in economic growth brought by the new leadership that will take office after the upcoming national congress of the Communist Party of China.

The market rally also tracked gains on Wall Street, which was bolstered by the European Central Bank's announcement of an emergency bond-buying program to assist debt-riddled eurozone countries. The Dow Jones Industrial Average jumped 244.52 points, or 1.87 percent, to 13,292.

Cement and coal shares rose the most Friday morning. Jiangxi Wannianqing Cement Co, the country's leading cement producer, jumped by the 10-percent daily trading limit to 11.06 yuan per share, while coal producer Yanzhou Coal Mining Co climbed 8.26 percent to 18.49 yuan.