SEOUL, AUG. 19 -- South Korea's ruling party called today for government mediation to prevent chaos in the face of a threatened strike by bus drivers this weekend in the nation's capital.

If the government does intervene, it will be the second time in two days that it has stepped into a labor dispute. Yesterday, the Labor Ministry recommended a three-point plan that ended two days of sometimes violent demonstrations by locked-out employes of Hyundai, the nation's leading industrial conglomerate.

Lee Min Sup, a spokesman for the ruling Democratic Justice Party, defended its proposal on the threatened bus strike as a necessary exception to President Chun Doo Hwan's declared principles for settling labor disputes.

"We have recommended the independent settlement of disputes between labor and management," Lee said, "but it is important for the government to intervene at an appropriate moment when independent settlements are impossible."

Negotiations in the bus dispute have failed to narrow the gap between the drivers' demand for a 28 percent wage increase and the 5 percent reportedly offered by the management of Seoul's privately owned bus companies.

In the Hyundai case, the Labor Ministry intervened with its three-point plan after lockouts drove the workers into a series of protests.

Government leaders, caught between the need to acknowledge widespread worker dissatisfaction and maintain public order, have called for peaceful settlements, and publicly recognized that blue-collar workers deserve a greater share in the country's economic growth.

The government also seemed to be listening to the will of the people when it reversed its position and endorsed new, broad-based labor unions in the Hyundai dispute.

Before the government moved to intervene, Chun cited independent settlements and a hands-off attitude as the heart of governmental policy in resolving the wave of labor disputes.