North Korea has abruptly cancelled a cultural event scheduled to be held jointly with the South, Seoul has said.
The events, and other links during the Games, were seen as a thawing of ties.
A telegram from the North reportedly blamed "biased" and "insulting" media coverage in the South. South Korea said the decision was "regrettable".
It said the North should uphold all the agreements that had been made.
Art performances and a taekwondo demonstration were among other events agreed with the North.
The South's unification ministry, quoted by the Yonhap news agency, said the North was also angry at media reports about a possible military parade it might hold on 8 February, a day before the opening of the Games.