Kumho Tire co-CEO Park Se-chang officially stepped down from his post Friday after its major creditors demanded his resignation, citing procedural problems in his appointment.

Park’s resignation came just three days after the company’s board of directors approved his promotion from senior vice president to CEO.

Another new co-CEO Lee Han-seop was removed from his post for similar reasons. The company, an affiliate of Kumho Asiana Group led by group chairman Park Sam-koo, now has only two CEOs including chairman Park and current president Kim Chang-kyu.

Early this week, the nation’s second-largest tire-maker named Park Se-chang, the son of chairman Park Sam-koo, and Lee as new CEOs.

But the tire firm’s major creditors, including Korea Development Bank and Woori Bank, collectively demanded his resignation.

The creditor banks, which together own 42.1 percent of the company’s shares, asserted that the company unilaterally carried out the leadership change without their approval.

Park, 40, paid a personal visit to KDB, Kumho Tire’s main creditor Thursday, and expressed his intention to resign, according to industry sources.

Park reportedly told KDB that he was “regretful that the company was unable to inform them of the decision in advance due to mistakes by the management.”

When Kumho Tire ended a four-year-long debt workout program it was placed under in December 2014, the firm had agreed to gain approval from its creditors, which are also its majority shareholders, prior to making key decisions or undertaking major leadership changes.

Kumho Tire has yet to announce its future course of action, including how to form its management leadership.

According to industry watchers, Park’s resignation is expected to deal a blow to the group’s efforts to regain ownership of the tire firm.

Since the firm emerged from its debt workout program, Kumho Asiana Group had been moving to strengthen the Park family’s hold in the tire firm’s management, they said.

By Sohn Ji-young (jys@heraldcorp.com)