Companies guilty of making telemarketing calls before 9 a.m. and after 10 p.m. could be fined VND20-40 million ($860-1,720), the ministry said in a draft regulation on spam calls, messages and emails.

Businesses which charge subscribers for receiving telemarketing calls will be fined VND10-20 million ($430-860).

Businesses which carry out telemarketing without informing the ministry will be fined VND60-80 million ($2,600-3,450).

There are around 10,000 phone numbers from which spam calls are made to millions of people every month, Minister of Information and Communications Nguyen Manh Hung told the National Assembly on Friday.

The ministry tested a tool last month to filter these phone calls and would continue to develop this tool, he said.

But 80 percent of these numbers are "junk" SIMs that not used by real persons, and selling these SIMs is the root of the problem and must be stopped, he added.

The ministry has been taking action though. In the last 10 months 75 percent of 24 million SIM cards that lack users’ information have been deactivated, he said.

The ministry blocked 90.4 million spam text messages in the first seven months of this year.

By the end of August, 2.6 million SIM cards which do not have complete user’s information have been locked.