The Japanese government announced a decision Sunday to expand a Japan-South Korea cooperation framework aimed at reducing emissions of methane from natural gas development projects.

Twenty-two Japanese companies, including Kansai Electric Power, Tokyo Gas and trader Mitsubishi, will newly join the framework, according to the government.

The government made the announcement at a meeting of liquefied natural gas producing and consuming countries in the city of Hiroshima.

Member companies on the procurement side will confirm efforts to reduce methane emissions by firms involved in natural gas production and urge them to disclose related information. Some firms have already given consent to the disclosure.

Methane's greenhouse effect is believed to be more than 20 times that of carbon dioxide. Leaks of methane from gas fields are a major issue that need to be dealt with.

The cooperation framework was announced at last year's meeting between LNG producing and consuming countries by Jera, a joint venture between the Tokyo Electric Power Company Holdings group and Chubu Electric Power and Korea Gas or KOGAS

The combined amount of LNG handled by Jera, KOGAS and the 22 new member companies a year stands at about 100 million tons, or some 25% of the total global LNG distribution volume. Information such as the amount of methane emissions from production facilities will be announced in an annual report.

Also at the Sunday meeting, the government-backed Japan Organization for Metals and Energy Security, or JOGMEC, and major Italian energy company ENI signed a memorandum of cooperation on diversifying LNG procurement sources.

The Japanese and Italian governments will shortly come up with a memorandum of cooperation for stable supplies of LNG.

Japan and South Korea agreed to conduct a test on LNG-related cooperation between the two countries' private sectors.