Blessing said the move was disclosed to his association by Britain's Home Office during a meeting in recent weeks.
Britain's Home Office declined comment, saying an announcement would have to be made to Parliament first possibly as soon as next month.
There was no indication of exactly how such a system would work or to what degree of judicial oversight would be involved, if any.
A Home Office spokesman insisted that any new surveillance program would not involve prying into the content of emails or voice conversations. "It's not about the content," the official said, speaking anonymously in line with office policy. "It's about the who, what, where and when."
In a statement, the Home Office said it's vital that police and intelligence services "are able to obtain communications data in certain circumstances to investigate serious crime and terrorism, and to protect the public."
Authorities already have access to a huge wealth of communications data, although the standards for retaining it differ depending on whether, for example, conversations are carried out over the phone, in an email, or over an instant messaging program.
Generally, authorities request such information during an investigation. A standardized mass-monitoring program capturing of every email, every post and every tweet would spell the creation of a formidable new surveillance regime.
"It is not focusing on terrorists or on criminals," Conservative lawmaker David Davis told the BBC. "It is absolutely everybody."
"Our freedom and privacy has been protected by using the courts by saying: 'If you want to intercept, if you want to look at something, fine. If it is a terrorist or a criminal, go and ask a magistrate and you'll get your approval.'
"You shouldn't go beyond that in a decent, civilized society, but that is what is being proposed."
Cost could be an issue as well.
Blessing said it would likely require the installation of tens of thousands of specialized pieces of hardware to monitor the country's Internet traffic. The price tag would run into the billions of pounds (dollars), a cost he said would either have to be borne by the taxpayer or by Internet service companies, who would in turn have little choice but to pass it on to their customers.
In either case, U.K. Internet users would be paying extra to allow their government to spy on them more effectively.
The revamped surveillance plans were first reported by Britain's The Sunday Times newspaper.