(Reuters) - North Korea's first official communication with the outside world following the death of leader Kim Jong-il and the transition of power to his son was a somber warning to South Korea and its allies that it would not change policies.

The main target of the message, delivered by state news agency KCNA Friday and attributed to the North's National Defence Commission, was South Korea's conservative government headed by President Lee Myung-bak, who has pursued a hardline stance against the isolated and impoverished North.

On this occasion, we solemnly declare with confidence that foolish politicians around the world including the puppet forces in South Korea should not expect any changes from us, said the commission, which was the top governing body under Kim Jong-il.

Under Kim Jong-il, who died earlier this month aged 69, North Korea conducted two nuclear tests. In 2010 it shelled a South Korean island and - most independent observers believe - sank a South Korean naval vessel.

The North denies the sinking and says it was provoked into the artillery barrage that killed civilians.

Kim Jong-il's son, Kim Jong-un, the third member of his family to rule North Korea, has made no public statements since the death of his father, whose vast funeral procession was held two days ago.

(Reporting by Seoul bureau; Editing by Ed Lane)