Around 18,000 unionized bank workers in South Korea joined a walkout Friday to protest the planned expansion of a performance-based pay system in the nation's financial industry, the government said.

It marks a far lower participating rate than the Korean Financial Industry Union expected.

Especially of note is that most of the employees at the four leading local banks -- Kookmin, Shinhan, KEB Hana and Woori -- stayed at work, according to the Financial Services Commission.

The KFIU, an umbrella union of roughly 100,000 members working at 15 commercial banks nationwide, went on a general strike at the Sangam World Cup Stadium in western Seoul. It's the union's first strike in two years.

Earlier, the union said a majority of members would take part in the collective action, adding it's aimed at protecting the stable operation of banking services.

But only 15 percent of the workers at the 15 banks participated in the walkout, the FSC said.

The Bank of Korea has already put an emergency response team in operation in a bid to minimize the impact to the financial system.

Employees at the central bank are not members of the union, but it shares computer and some other financial transaction networks with the commercial banks.

The KFIU claims it has no other choice to protest against the scheme for a full-scale performance-linked salary mechanism, saying it will be used to allow banks to fire more employees and eventually lower the competitiveness of the banking sector.

"We can't accept the dismissal salary system forced by the administration even with a knife under our necks," said Kim Moon-ho, head of the union. "It will seriously harm the stability of the financial industry and bring irreversible damage to the people."

The union will consider additional collective actions after the one-day general strike, he added.

Government officials have stressed that merit-based pay is a must to help ride out a crisis facing the financial sector, mainly caused by prolonged low economic growth and interest rates.

The government is open to talks with bank workers on detailed ways of implementing it, they added. (Yonhap)