MANILA, June 21 (Xinhua) -- Negotiations to end the decades-old leftist insurgency in the Philippines face uncertainty anew as the government suspends "all backchannel talks" for three months to review its position, a government negotiator said on Thursday.

Hernani Braganza, the government negotiator for backchannel talks, said the Duterte administration has decided "to suspend all backchannel talks" with the insurgents "pending the three month review of all signed agreements related to the negotiations."

Braganza said the rebel panel has already been officially informed about the government's decision during a three-day meeting which ended on Wednesday in Utrecht, the Netherlands.

The meeting was witnessed by third-party facilitators from the Norwegian government led by Special Envoy Idun Tvedt. Norway has been brokering the on-and-off talks.

However, Braganza said the suspension "does not preclude communications between the two parties if deemed necessary."

The Utrecht meeting was called to explain to the rebels the government's decision to postpone the mutually approved schedule of the formal meetings in the peace negotiations to take place in Oslo, Norway on June 28 to 30, according to a separate statement issued by the National Democratic Front of the Philippines (NDFP) panel head Fidel Agcaoili.

"The NDFP team listened to the explanation of the government team on the reasons for postponing the resumption of the formal talks and agreed that the peace negotiations continue despite the cancellation of the scheduled formal talks in Oslo on June 28 to 30," Agcaoili said.

He added the agreements reached in the four rounds of informal talks in March, April, May and June 2018, "remain valid and have the effect of continuing the peace negotiations under the direction of the principals and reaffirmation of previous agreements."

The Philippines announced last week that it was pushing back peace talks with the communist rebels scheduled on June 28, saying President Rodrigo Duterte wanted a wider public consultation before restarting formal talks.

Duterte's decision came after defense and military officials expressed concern that the rebels might use the talks to consolidate its forces on the ground.

Since 1986, the government has been trying to reach a peace deal with the leftist rebels but has so far failed to reach a formal agreement.

The leftist rebellion began in 1969 and reached its peak in 1987 when it boasted 26,000 armed guerrillas. At present the military estimates the armed rebels at around 4,000.