The government has announced measures intended to enhance transparency in the accounting of labor unions.

The labor ministry on Thursday issued 40-day advance legislation notices for related revisions to enforcement ordinances under the labor union and income tax laws, which are set to be approved by the Cabinet in August before taking effect in January.

Under the revisions, union dues will receive a tax credit of up to 30 percent only if union ledgers are made public via the ministry's system by April 30 every year.

The revised rule applies to unions with membership of one-thousand or more, including affiliates. The nation's two umbrella unions that take some of the union dues will also be subject to the rule.

In order to improve the professionalism of the unions' auditors, only those that have experience or expertise in finance or accounting duties will be given the role, while auditing can be conducted upon request by over a third of union members.

The Federation of Korean Trade Unions accused the government of attempting to threaten and humiliate the unions, while the Korean Confederation of Trade Unions called for the withdrawal of what it called "unconstitutional and illegal" revisions.