The Communist Party of the Philippines says it has directed its armed unit, the New People's Army, to go on an offensive nationwide.
In a statement issued Sunday, the CPP also said it would consider forming an alliance with any of the parties seeking to oust President Gloria Macapagal Arroyo from power. The CPP said its list of potential allies include disgruntled military and police units and conservative political parties.
On Friday, President Arroyo declared that government troops would observe four days of unilateral cease-fire with communist rebels to mark the Christian holiday season. The days of the cease-fire are Christmas Eve, Christmas Day, New Year's Eve and New Year's Day.
The government and communist rebels have been engaged in armed conflict for more than 40 years.
Some information for this report provided by AFP and AP.