The Democratic People's Republic of Korea will not negotiate with the United States over two US citizens it is holding until former detainee Kenneth Bae stops publicly talking about his time in prison, state media said on Monday.

Pyongyang arrested Bae, a US missionary, in November 2012 and sentenced him to 15 years' hard labor for crimes against the state.

He was released two years later and has written an account of his detention in a memoir released in May. Since then, Bae has spoken about his experiences at several public appearances and given interviews to promote the book.