BEIJING (REUTERS) - Beijing has eased a push to convert northern cities to gas or electric heating after two provinces warned of gas shortages, and reports of freezing classrooms deepened concerns about a winter heating crisis, local media said on Thursday (Dec 7).

China's Ministry of Environment has told northern regions that have not converted to gas or electric heating to continue using coal or other fuels, financial magazine Caixin reported.

The ministry issued a document with the instructions on Thursday, the magazine said, citing regulatory sources.

Areas that have made the switch should ensure a supply as well as stable prices of gas and electricity, the ministry said in the document, according to the magazine.

The report comes after official English-language paper China Daily said the Ministry of Education has demanded "immediate" action to ensure school classrooms are warm enough after media reports that students showed symptoms of frostbite due to delays in heating supplies in Hebei provinces.

Heating to some rural primary schools in Hebei's Quyang country has been delayed, forcing students to attend classes outside in the sun in a bid to keep warm, the China Youth Daily reported.