NOORDJWIJK, The Netherlands (UPDATE 2) - Government suspended anew peace negotiations between the government and the National Democratic Front of the Philippines (NDFP), with President Rodrigo Duterte's top peace adviser citing continuing offensives by communist rebels against government troops.

In a press conference, Presidential Peace Adviser Jesus Dureza said the administration "will not proceed to participate in the scheduled fifth round of peace negotiations until such time as there are clear indications that an enabling environment conducive to achieving just and sustainable peace in the land . . . shall prevail."

The rebel leadership's directive for troops to step up attacks in the face of martial law in Mindanao is a "defiant, blatant, and serious challenge" to President Rodrigo Duterte's authority, Dureza said.

"We question the sincerity of the CPP/NPA/NDFP, if they truly are in pursuit of peaceful coexistence. The Duterte administration would rather pursue the path of genuine dialogue to build a nation worthy of its citizens," Presidential Spokesman Ernesto Abella said in a statement.

The two sides were supposed to hold the fifth round of negotiations, aimed at ending a nearly five decade-long Maoist insurgency that has claimed thousands of lives.

"We are still hopeful na makapag usap ulit para pag usapan yung patuloy ng peace talks," government peace panel member Hernani Braganza said.

(We are hopeful that we can talk again to discuss the continuation of the peace talks.)

NDFP senior adviser Luis Jalandoni was first to break the news to the media, saying: "[The negotiation] has been cancelled by the GRP (government) panel."

Asked why the government moved for the halt, Jalandoni said: "Ang sabi nila continuing NPA (New People's Army). offensives pero ang mali doon, hindi nila binabanggit concrete reality on the ground that requires the NPA to defend the people on the ground."

The NPA is the NDFP's armed wing.

It was the second time for the talks to hit a roadblock under the administration of President Rodrigo Duterte, who had vowed to pursue peace talks with rebel groups, including communist and Moro rebels.

Duterte had suspended the talks in February.

The second suspension in talks happened just as another NPA attack was reported Saturday morning in Bukidnon, which left two civilian auxiliary officers wounded.

In his statement, Dureza cited "serious challenges" that must be addressed before the talks could proceed, including "the noticeable upscale of incidents of offensive attacks throughout the country."

He also cited the "seeming" public perception that the NPA offensives were an "open and public defiance of President [Rodrigo] Duterte."

The official also cited earlier statements by communist leaders that "they have no control over their forces on the ground."

Dureza also cited as "the most serious development" the communist leadership's "blatant publicly announced decision... to accelerate and intensify attacks against the government in the face of martial law in Mindanao."

Duterte had placed Mindanao under martial law after gunfights erupted between government troops and the terrorist Maute and Abu Sayyaf groups in Marawi City on Tuesday.

Operations are ongoing to quell the rampage of local terrorists, who the President said aimed to create an Islamic province in Mindanao.