South and North Korea will likely hold bilateral negotiations on the opening day of the working-group nuclear talks in Beijing on Wednesday.

A government official said Tuesday that it has become customary for the two Koreas to make bilateral contact on the sidelines of six-way nuclear talks.

Another government official said six nations attending the working-group talks will also likely hold unofficial bilateral negotiations among themselves on the opening day.

It is yet unclear whether planned bilateral talks between North Korea and the United States as well as between North Korea and Japan will take place before Wednesday.