Updated

U.S. Secretary of State John Kerry says he expects peace talks for South Sudan to begin as planned, despite reluctance by the top rebel leader who has called immediate negotiations premature and meaningless.

Speaking to reporters Monday in the Angola capital before heading back to the U.S., Kerry also sharpened the threat of sanctions or deploying new U.S. troops to South Sudan should the talks fall through.

Rebel leader Riek Machar has told reporters that he does not see the point of peace talks that would lead to a transitional government before elections. Kerry says he's aware of the comments but insists the rebel leader did not outright reject the talks.

Meanwhile, South Sudan's military wrested a base and a town from rebel control in a violent counteroffensive just days the president agreed to participate in the talks.