A labor group said today it will stage a four-day strike this week to demand a shorter work week and to protest a possible takeover of an ailing South Korean carmaker by a foreign investor.

The Korean Confederation of Trade Unions asked its 500,000 members to walk off their jobs from Wednesday to Saturday, officials said.

“The economy has recovered. We believe it is only fair for the authorities to guarantee the very basic rights of workers now,” said Sohn Nak-koo, a spokesman for the confederation.

Sohn said his group gave the government until Sunday to accept its demands. The confederation will consider prolonging the strike if the demands are not met, he said.

The labor group, with members in the car and shipbuilding industries, is demanding that the work week be cut from 44 hours to 40 hours, without a cut in pay. Major businesses are opposed to a shorter work week.

“Considering our national economic status, it is too early to shorten the work week,” said Ko Yong-yi, a spokesman for the Federation of Korean Industries, a lobby for major businesses.

The government earlier said it would submit a bill to the National Assembly this year to shorten the work week, but with a precondition that the government, businesses and labor groups reach an agreement on the issue first.

The confederation rejects meeting the other parties.

“The confederation’s strike has no cause. We asked them to resolve the matter through talks, but they refuse to do so,” said Chung Min-oh, a spokesman for the Labor Ministry.

Chung said the government, businesses and the Federation of Korean Trade Unions, the nation’s largest labor group with 1.2 million members, began discussing the issue last week.

The meeting will continue with or without the participation of the confederation, he said.

The confederation is also demanding the government stop a plan by domestic creditor banks to sell ailing Daewoo Motor Co. to a foreign investor, fearing it would lead to mass layoffs.

Last year, Daewoo Motor lost $3.9 billion on revenues of $5 billion. Creditors demanded a major overhaul, and a restructuring committee started seeking a savior.

While GM and Ford are considered the front-runners in international bidding for Daewoo Motor, DaimlerChrysler AG [NYSE:DAJ], Fiat SpA and Hyundai Motor Corp. have expressed interest.

A successful bidder will be chosen by September.