The BBC could be made to share part of the television licence fee with commercial rivals under government plans to be announced later.
The Digital Britain report will suggest ways to help companies like Channel 4 cope with the impact of the internet.
It is also expected to include plans to tackle illegal file-sharing and to bring broadband to the whole country.
Gordon Brown said fast internet was now "an essential service, as indispensable as electricity, gas and water".
In October 2008, Minister for Communications Lord Carter began work on a plan aimed at securing the UK's place at the head of the new media age.
Among 22 specific actions announced in his interim report in January was a commitment to establishing a universal broadband service for every home and business by 2012.
Writing in the Times newspaper on Tuesday, the prime minister reaffirmed his commitment to that "transformation".
"We also need to help Channel 4 to secure its future"
"Digital Britain cannot be a two-tier Britain - with those who can take full advantage of being online and those who can't," he said.
As well as looking at opportunities, the Digital Britain report will also try to tackle threats presented by new technology.
Local newspapers and television stations have both suffered significant losses in revenue thanks to the internet, but Mr Brown insisted their journalism must be protected.
"We cannot allow a monopoly to take root," he wrote.
"We also need to help Channel 4 to secure its future... it now requires long-term stability to develop as a truly global player."
The BBC's media correspondent Torin Douglas said Lord Carter believed the licence fee could be a possible answer to the woes of commercial broadcasters.
At present, more than ?100m a year is earmarked to help the elderly switch to digital TV and any left over could help pay for wider broadband access or local news on ITV, our correspondent added.
But the BBC Trust has said that if any money is left over from the digital switchover, it might be better returned to licence-payers.