The instruction went out on Thursday in a letter signed by Bangladesh Telecommunication Regulatory Commission (BTRC) Senior Assistant Director Sabina Islam.
The letter said the order would remain in force starting from 6pm on Thursday until further orders.
But, IIG operator Fiber at Home official Sumon Ahmed said the instruction would hurt the internet service.
Internet Service Providers Association President Aktaruzzaman Manju said their clients were facing troubles in uploading data.
He said they were receiving complaints from the subscribers and that it should be withdrawn.
However, banks, financial institutions, software firms, travel agents, embassies and government organisations will be exempted from the cut. But lists of such organisations and agencies have to be sent to BTRC in seven days.
BTRC says the instruction will not impact download from internet.
An official of the watchdog’s Engineering and Operation Division said the instruction had been made to prevent illegal VoIP on a trial basis.