The National Audit Office (NAO) said Sunday that it is auditing the country's top three steel companies to ensure that they have implemented a steel industry plan issued in 2009.

China published the Blueprint for the Adjustment and Revitalization of the Steel Industry during the financial crisis in an effort to halt haphazard investment and redundant construction, increase industry concentration and enhance the competitiveness of Chinese steel companies.

The auditees are the Baosteel Group Corp, the Wuhan Iron and Steel (Group) Corp, and the Angang Steel Co All three companies rank among the world's top ten steel producers in terms of output.

"Auditing the three companies is one of the NAO's major tasks this year," said Wei Qiang, head of the NAO's Enterprise Audit Department.

The NAO started on-site audits of the three firms in June and is expected to complete them soon, Wei said.

The main objectives of the audits are to see how well the companies have implemented the blueprint and what problems they have met, as this will help the government to perfect its policies and further promote the development of China's steel industry, Wei said.