Philippine negotiators and communist guerrillas are set to resume peace talks in Rome, with the Maoist insurgents warning that alleged government violations of an accord on human rights may prompt them to end a monthslong ceasefire.

The presidential adviser to the talks, Jesus Dureza, said the government is optimistic "with managed expectations" about the resumption of the Norway-brokered negotiations beginning Thursday in the Italian capital.

Rebel chief negotiator Fidel Agcaoili was less optimistic, saying the guerrillas have raised a number of complaints, including alleged government breaches of a 1998 accord on respecting human rights and another pact on the safety of guerrilla consultants.

Agcaoili says the complaints, including the failure to release nearly 400 detainees the rebels consider political prisoners, made extending a five-month cease-fire "untenable."