Suh Byung-jo, director general at the Ministry of Information and Communication said "We feel obliged to come up with measures to counter the recent woes caused by adult video clips available on the internet," according to The Korea Times.

A small number of pornographic video clips were posted to Yahoo Korea earlier this month. Popular portal Daum also briefly hosted some content that caused an upset even though (from the description) it would be acceptable for broadcast TV in many western countries.

The Ministry plans to work with ISPs to block all major overseas porn sites by the end of the year.

"[I]t will be a tall task to block every porn site. But we think we have to be able to cut access to a nasty site when our people report it," The Korea Times quoted Suh.

South Korea is often cited as a leader in the provision of very high speed Internet access.

According to reports, most of the banned foreign sites are US based. It seems unlikely that the decision will spark a trade dispute between the two countries.