The BBC is examining plans to build an internet portal to stream its films and programmes down telecom lines on a pay-per-view basis.

The move would represent one of the most ambitious attempts by the corporation to develop its commercial operations since the Government charged it with finding new sources of income at the start of this year.

Last week beeb.com, the corporation's e-commerce portal, received a £32.5 million cash injection from US venture capital firm TH Lee Global Internet Managers. The deal values beeb.com and its free internet service provider, beeb.net, at £240m. In the coming months the BBC is to embark on a £7m publicity drive to attract visitors to the two sites. But the corporation also wants to start distributing its vast content via the internet.

The BBC has been trying out online video-on-demand services in conjunction with internet firm Yes Television since the start of this year. The deal allows Yes to deliver 600 hours of BBC archive programming over the internet over the next two years. But the corporation is now looking to create its own separate content delivery portal.

In an interview in today's Observer, Rupert Gavin, chief executive of BBC Worldwide, the corporation's commercial arm, said the plans could play an important part in helping develop future earnings streams. The two portals would cross-promote.

Critics charge that the BBC is in danger of becoming too commercial, but Gavin said the extra revenues generated online would be ploughed back into public-sector broadcasting commitments.