BEIJING (Reuters) - China's Premier Li Keqiang has pledged to take further steps to boost private investment and lower borrowing costs for companies, state radio reported on Tuesday.

The government will use pro-active fiscal policy to boost investment and continue to promote public-private partnership in investment projects, Li said.

The cabinet has unveiled detailed measures, including widening financing channels for firms and establishing new equity funds, to support investment and economic growth.

China's economy expanded slightly faster than expected in the second quarter but private investment growth shrank to a record low, suggesting future weakness which could pressure the government to introduce more support measures.

(Reporting by Kevin Yao; Editing by Robert Birsel)