A senior Philippine cabinet official says President Gloria Arroyo has approved the lifting of martial law in a southern province, where 57 people were massacred last month in the country's worst instance of political violence

Executive Secretary Eduardo Ermita told a news conference that the martial law edict will be lifted at nine pm (1400 UTC) on Saturday.

He said the decision was taken after a Cabinet recommendation.

The week-long martial law edict authorized a massive military and police operation against the ruling Ampatuan clan blamed for the killings of members of a rival family and 30 journalists.

Large stashes of weapons were seized and more than 60 people allied with the Ampatuan family were detained.

Demonstrators rallied in several Philippine cities on Thursday to protest the imposition of martial law, which allows troops to make arrests without warrants. 

Some information for this report was provided by AP and Reuters.