BEIJING - China on Thursday announced a decision to expand the coverage of the country's healthcare insurance system to include the treatment of critical illnesses, aiming to prevent patients from being reduced to poverty by necessary healthcare costs.

The fresh systematic arrangement will further increase the level of protection that China's healthcare insurance system can offer, according to an official document co-issued by the National Development and Reform Commission and five other central government departments.

Sun Zhigang, head of the health reform office under the State Council, China's Cabinet, said it aims to ensure that each patient's total medical expenditure is no more than the "catastrophic household expenditure for healthcare," which is set at the level of the regional annual per capita disposable or net income.

In an interview with Xinhua, Sun said when a patient's medical bills for necessary treatments under the existing basic healthcare insurance system exceed that level, he or she will receive reimbursements from the newly-launched critical illness insurance scheme.

Though around 1.3 billion people, or more than 95 percent of China's population, have been covered by the healthcare insurance system by the end of last year, medical expenditure burdens incurred by patients with severe medical conditions remain heavy, Sun said.

"The new move targets the widely-complained problem of 'people falling into poverty due to illnesses,' and aims to ensure that most people won't be reduced to poverty because of diseases," Sun said.

Local governments have been asked to design local regulations on fund raising, reimbursement portions and other details regarding the new insurance scheme in line with local conditions, according to the document.

Qualified commercial insurers will be selected to operate the critical illness insurance program through bidding, the document said.