Thai information and communications technology minister Mun Patanotai (pictured) also advised web providers to block an additional 1,200 sites that allegedly breach the Computer Crime Act.
The government says that, of the 400 sites highlighted for shutdown, 344 include content that is damaging to the Thai royal family, while the remaining sites include religious or obscene undertones.
The request comes as Thailand is under a state of emergency following a week of violence and tension that has seen thousands of protesters demanding the resignation of prime minister Samak Sundaravej.
The government says that, of the 400 sites highlighted for shutdown, 344 include content that is damaging to the Thai royal family, while the remaining sites include religious or obscene undertones.
The request comes as Thailand is under a state of emergency following a week of violence and tension that has seen thousands of protesters demanding the resignation of prime minister Samak Sundaravej.