The Obama administration is launching a virtual embassy for Iran more than three decades after the bricks and mortar mission in Tehran was closed and diplomatic relations severed following the 1979 Islamic revolution and hostage crisis.

The web-based "embassy" went online om Tuesday with versions in English and Farsi explaining why the administration has chosen this method of reaching out to the Iranian people.

In a video message posted to the sites, Secretary of State Hillary Rodham Clinton said the lack of diplomatic relations had hindered dialogue between the US and Iranian citizens.

Clinton said the online embassy was an effort to use new technology to bridge those gaps and promote greater understanding between the two countries.