Bangladesh on Thursday defended its new labour laws, and said it was angry at criticism from the International Labour Organisation (ILO) which called the legislation inadequate.
Parliament passed the legislation last week in the wake of a garment factory disaster in April that killed 1,129 people, highlighting poor safety standards in the industry.
Lawmakers said the new law ensured full trade union rights" for millions of labourers, as it scrapped previous provisions requiring factory owners to approve the formation of a union.
In a statement issued on Monday, however, the ILO said that the law fell short of "several important steps called for" by the organisation, notably related to restrictions on workers' freedom of association.
The law stipulates that workers can only form a union if 30 percent of employees approve of it in advance.
On Thursday Bangladeshi officials told a press briefing that Dhaka had vented its anger at the ILO over the public criticism.
"We've protested," Labour Minister Rajiuddin Ahmed Raju said. "It's not acceptable. We're writing a letter seeking explanation as to why this kind of statement was issued."
Bangladesh, the world's second largest garment exporter, has been under intense international pressure to overhaul labour laws since the April 24 tragedy, one of the world's worst industrial disasters.
The garment industry, which relies on cheap labour to keep itself competitive, is the mainstay of the economy, making up 40 percent of its industrial workforce and 80 percent of its $25 billion annual exports.
The United States last month cancelled a trade privilege for Bangladesh, alleging that it had not done enough to ensure workplace safety.
There was no immediate reaction from the US or the European Union, who together account for some 80 percent of Bangladesh's $21.5 billion garment exports, to the new law.
Washington last week outlined an action plan for Dhaka to restore the privilege, saying it should implement new laws that offer freedom of association and collective bargaining.
Raju defended the requirement for 30 percent of the workforce to approve formation of a union.
"If you don't have support of 30 percent of the employees, you don't have any right to form a union," he said.