SEOUL: South Korea's fourth-largest conglomerate LG Group said its Chairman Koo Bon-moo passed away on Sunday due to illness.

Koo, 73, had been struggling with an illness for a year, LG Group said in a statement.

"Becoming the third chairman of LG at the age of 50 in 1995, Koo established key three businesses - electronics, chemicals and telecommunications - led a global company LG, and contributed to driving (South Korea's) industrial competitiveness and national economic development," LG said.

A group official said Koo had been unwell for a year and had undergone surgery. The official declined to be named due to the sensitivity of the matter.

Prior to its chairman's death, LG Group had established a holding company in order to streamline ownership structure and begin the process of succession.

LG Corp, a holding company of the electronics-to-chemicals conglomerate, said on Thursday its longtime chairman was unwell and planned to nominate his son to its board of directors in preparation for a leadership succession.

Heir apparent Koo Kwang-mo is from the fourth generation of LG Group's controlling family. He owns 6 percent of LG Corp and works as a senior official at LG Electronics Inc.

The senior Koo's funeral will be held privately at the request of the family, the company said.