The chat room of www.pantip.com was taken offline on Sunday after authorities ordered a temporary closure.
Vissanu Meeyoo, an IT ministry spokesman, said the online forum often posted criticisms against the military-installed government leaders.
The site initially posted a notice saying that its political forum, known as the Rajdamnoen Room, was suspended at the ministry's request for "national security" reasons. The notice was later withdrawn.
Unfounded
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Insulting the king is a serious criminal
offence in Thailand [EPA] |
The forum is named for an area in central Bangkok that has historically been the center of pro-democracy protests.
Wanchat Padungrat, the site's founder, said he found no postings that insulted the monarchy and did not understand the reason for the ban, The Nation newspaper quoted him as saying on Monday.
He suggested that the military-installed government may have been offended by anti-coup postings instead given the lack of specifics on the allegedly offensive postings.
Google Inc., YouTube's owner, has refused to remove the videos but says it is working with the Thai government to resolve the impasse.
A crime
Also on Monday, pantip.com urged members to post messages condemning Google for not removing the video clips that mocked the king.
More than 1,000 people had posted messages, including one that said Google's reaction had "really hurt the people of Thailand" and showed a lack of respect for the country's culture and traditions.
Insulting the monarchy in Thailand is a criminal offense known as lese majeste.
Last month, a Swiss man was imprisoned for 10 years for vandalising portraits of the king in northern Thailand.
The YouTube ban has drawn sharp reactions from critics and proponents in Thailand.
Some have criticised the ban as a violation of freedom of expression and another sign of censorship by the government which took over after a coup ousted Thaksin Shinawatra as prime minister.