The paper, quoted by KCNA Rodong Sinmun said the "actions are as rude as blindfolding people's eyes and stopping their ears and mouths".
The ban showed South Korea was against reconciliation with the North, the newspaper added.
South Korea's unification ministry said this month that it had no plans to lift the ban.
North Korea is one of the few countries to be virtually completely cut off from the internet, with just a few thousand carefully vetted individuals allowed access.
Kim Jong-il and other senior members of the government are said to be online via connections to China.
In contrast South Korea is one of the world's most wired countries, with three-quarters of the population having access to the internet.