BEIJING, April 3 -- China will continue its cautious approach and prioritize safety in investment of the national social security fund, vice finance minister Wang Baoan has stressed.

Wang made the remarks at a press briefing on Friday, after China's State Council announced earlier this week a broader investment scope for the social security fund to increase returns.

Wang said a certain safety line should be drawn as a precondition for seeking higher yields.

Founded in 2000, the national social security fund is designed to solve China's aging problem as well as being a strategic reserve to support future social security expenditure.

The funding sources include fiscal allocation from the central government, allocation from the lottery public welfare proceeds, individual contributions and capital raised by other methods approved by the State Council.

As China faces a huge challenge in caring for its increasingly large elderly population, experts have repeatedly called for the opening of new investment channels for the funds.

Official data showed the fund gained 22.7 billion U.S. dollars from investment in 2014, with an 11.4-percent return on investment.