Washington, Jun 21 (IANS): Al Qaeda has posted a new video on Islamist websites where a spokesman of the militant outfit calls US President Barack Obama "snakelike" and a "treacherous, bloodthirsty and narrow-minded American war president".

In the video posted Sunday, American-origin Al Qaeda spokesman Adam Gadahn criticises the US' "aggression and interference" in Afghanistan, Pakistan, Yemen and Somalia, the CNN reported.

Gadahn speaks in English and the video features Arabic subtitles.

Addressing Obama, Gadahn says: "I know that as you slither snakelike into the second year of your reign as a purported president of change. You are fighting, your hands full, with running the affairs of a declining and besieged empire, and in the process proving yourself to be nothing more than another treacherous, bloodthirsty and narrow-minded American war president".

The authenticity of the 24-minute video, carrying the name of as-Sahab, Al Qaeda's media arm, however, could not be verified.

The Al Qaeda leader says should America continue to "ravage our countries, interfere in our affairs and trample on our dignity, liberty and sovereignty", it can guarantee for itself "a future of misery, insecurity and ultimately defeat".

The US has offered a $1 million reward for information leading to the capture of Gadahn, the first American charged with treason since 1952.