China's central regulators have released two guidelines in the past three months to tackle corporate bond defaults that took place from last year to the beginning of this year.

The National Development and Reform Commission issued an announcement on its official website on Tuesday to urge local authorities to check companies' ability to repay their bonds. Comprehensive investigations should be conducted to avoid risks.

The announcement came one day after the suspension from trading of a corporate bond issued by China Minsheng Investment Group, which is a private equity group backed by many of China's leading privately-owned enterprises. The group had already made a technical default on Jan 29 by missing the deadline to repay principal on a 3-billion-yuan ($44 million) private placement bond.

But the group's president Lyu Benxian said that such difficulties are acceptable for the four-year-old company which is still "in its infancy". The group will make major breakthroughs soon by introducing strategic investors and withdraw from the projects which are not in line with the group's strategic transformation, he said.

However, statistics from Financial China Information & Technology showed that there have been 15 reported corporate bond defaults so far this year, with the total amount exceeding 10 billion yuan. Coal miner Win-time Energy reported the largest default of 1.07 billion yuan on Jan 22. Construction industry leader Beijing Orient triggered a technical default on Tuesday by making the repayment one day later than the due date.

According to Guotai Junan Securities, there were a total of 165 corporate bond defaults last year. The total amount hit a historic high of over 150 billion yuan, which was much higher than the aggregated default amount registered from 2014 to 2017.

Privately owned enterprises were responsible for the majority 126 defaults last year, with the total amount exceeding 113.6 billion yuan. Qin Han, chief analyst for fixed income products at Guotai Junan, said internal management problems were the major factor.

"Corporate strategy, investment decisions and internal control system issues caused these defaults," he said.

As estimated by China International Capital Corp Ltd, the total repayment amount of corporate bonds will hit a record high this year of 6 trillion yuan, up 15 percent from a year earlier. But Liu Yan, deputy research head at Beijing-based China Lianhe Credit Rating, said that there will not be a noticeable increase of corporate bond defaults this year.

"There is a negative correlation between the default rate and economic growth based on past experience. Market liquidity will be relatively abundant this year and therefore companies' financing environment will be better," said Liu.

Apart from the necessary investigation, the NDRC also said in the announcement on Tuesday that it would encourage qualified firms to issue bonds to support infrastructure construction projects.