And,the countries relationship changed again as China became a major trading partner.

VOA: special.2010.03.03

China is North Korea's only ally and major trading partner, but has grown increasingly frustrated with its growing belligerence.

BBC: Kerry hails Chinese North Korea pledge

The rise in our sales to China were faster than our sales rise to any other major trading partner.

BBC: Can Germany afford eurozone collapse?

He will spend time in Seoul and Tokyo as well as in Beijing, North Korea's last remaining ally and its major trading partner.

BBC: North Korea: US urges China to rein in Pyongyang