The United States on Thursday criticized a Pakistani court's overturning of a death sentence handed down over the gruesome killing of American journalist Daniel Pearl, calling the decision an "affront."

"The overturning of the convictions for Daniel Pearl's murder is an affront to victims of terrorism everywhere," said Alice Wells, the top US diplomat for South Asia.

She welcomed indications that Pakistani prosecutors would appeal the decision on British-born militant Ahmed Omar Saeed Sheikh.

"Those responsible for Daniel's heinous kidnapping and murder must face the full measure of justice," Wells wrote on Twitter.