A draft bill proposed by Fidesz would see a rise in the amount of overtime that employers can demand from workers, along with an extended time period for settling compensation.
Union leaders claim that the so-called "slave law" proposals underline the intention of Orban's government to increase corporate profits at the expense of workers.
Several thousand people protested in front of the Hungarian parliament building to show their opposition.
"In Hungary, we carry the largest burden on our back and, in return, we get the lowest wage in Europe," Laszlo Kordas, president of the Hungarian Trade Union Confederation, told protesters.
Low wages as leverage?The new rules mean workers could accrue up to 400 hours of overtime instead of the current 250-hour maximum. Employers would also have three years to compensate employees with either payment or time off work, instead of the current one year.
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Although employers would need workers to agree to the additional hours, unions say employers would use low wages to pressure employees into accepting. Critics also object to a proposal that overtime arrangements should be agreed with individual workers, bypassing collective bargaining arrangements.
"This process is only about the suppression of employee interests and the prioritization of the interests of employers and the powers that be," said Jozsef Szilagyi, co-chair of the Democratic League of Independent Trade Unions.
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The government says greater labor flexibility is needed to satisfy investors — such as German car companies whose factories have helped drive economic growth.
Critics have speculated that German auto giants have lobbied Budapest to loosen overtime restrictions. However, the German-Hungarian Chamber of Industry and Commerce has denied that German firms have called for the changes.
rc/aw (Reuters, AFP, AP, dpa)
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