Tokyo, Aug 25 (IANS): Japan on Friday approved the freezing of assets of additional foreign firms, due to their links with North Korea, which includes adopting new unilateral sanctions.

The sanctions affect four Chinese and two Namibian companies, as well as one Chinese and one North Korean national, adding to the measures announced by Japan in July, a government spokesperson told Efe news.

Tokyo's decision involves freezing the assets of those believed to be collaborating with the North Korean regime in exporting coal and sending labour abroad, and is meant to curb capital inflows into the rogue nation, in response to its military program escalation.

As a punishment to those associated with the Pyongyang regime's weapons programs or raw materials trade, Tokyo already included five companies and nine individuals from China on the list in late July.

Japan's Chief Cabinet Secretary Yoshihide Suga said during a press conference on Friday here, that Japan believes it is extremely important to pressure North Korea, along with the United States and South Korea.

Tokyo's decision to expand its list comes after Washington announced on Tuesday the freezing of assets and banning financial transactions with more than fifteen Chinese and Russian entities and individuals for their association with North Korea.

Beijing has opposed the imposition of unilateral sanctions by any country outside the framework of the UN.

The UN Security Council approved new sanctions against North Korea earlier this month, imposed for the rogue state's two intercontinental missile tests in July, which could reduce Pyongyang's annual export revenue by $1 billion.