MANILA (Reuters) - Philippine government peace negotiators cancelled formal peace talks with Maoist-led rebels in the Netherlands on Saturday after New People’s Army (NPA) guerrillas stepped up offensives in the countryside.

The two sides have been engaged in peace talks brokered by Norway to end nearly five decades of conflict, in which more than 40,000 people have been killed.

At the latest round of talks with the National Democratic Front, the NPA’s political arm, presidential adviser Jesus Dureza said the government had suspended negotiations because the rebels did not reciprocate President Rodrigo Duterte’s peace overtures.

Reading a prepared statement, Dureza said talks would resume only when there were “clear indications that an enabling environment conducive to achieving a just and sustainable peace in the land through peace negotiations across this table shall prevail”.

Dureza said the decision was taken when rebel leaders ordered guerrillas to “accelerate offensives” after martial law was declared on Tuesday night on a southern island, in response to the seizure of a city by Islamist Maute group militants.

The Maute militants are not connected to the NDF.

It is the second time the government has halted peace talks with communist rebels over guerrilla attacks on military targets and businesses, such as mines and plantations.

Duterte is eager to strike a peace deal with the communists but is angered by continued violence. He says their demands are excessive and that he has already made concessions.

The suspension comes as fears grow over the rise of radicalism in the Muslim parts of the southern Philippines.

The rebels’ chief negotiator, Luis Jalandoni, said the government’s demand to stop guerrilla attacks was “ridiculous” and “unacceptable” because soldiers were attacking rural communities where rebels are based.

“The military should stop its violations of human rights and international humanitarian law. These are unacceptable to us,” he told reporters.

Dureza said Duterte has tried hard to secure peace by freeing more than 20 rebel leaders and declaring a unilateral ceasefire.

He said the government was open to holding “localised peace negotiations” because the rebel leaders, some of whom live in exile overseas, say they are losing control over guerrilla forces on the ground.