(UPDATED) Preliminary talks between the Communist Party of the Philippines (CPP) and peace negotiators designated by President-elect Rodrigo Duterte have commenced in Oslo, Norway.

Labor Secretary Silvestre Bello, Duterte peace adviser Jesus Dureza and former congressman Hernani Braganza -- all veteran peace negotiators -- met with leaders of the CPP's political wing, the National Democratic Front of the Philippines (NDFP), to prepare for the expected resumption of peace talks in July.

CPP-NDF leaders were all present in the meeting, including CPP founder Jose Maria Sison, NDFP negotiating panel head Luis Jalandoni and NDF spokesperson Fidel Agcaoili.

The informal talks started at 5 p.m. on June 14 at Leysebu Hotel at the outskirts of Oslo and ended at 11 p.m. over dinner, according to Dureza.

The meeting comes after two trust-building measures initiated by Duterte: a guarantee to release of all political prisoners and an offer of Cabinet posts for Communist leaders.

In his opening statement, Sison expressed confidence that peace talks will flow more smoothly under a Duterte presidency. He described Duterte as a revolutionary who espouses socialism and is for the working class.

Dureza, meanwhile, said he is hoping that communist leaders will keep faith with the Duterte government so that peace can be achieved while public confidence in the President-elect remains high.

"The ambiance of our initial meeting is good because it's been four years since our negotiations got stalled. And Mr. Joma Sison and his colleagues have met with us already for peace talks in the Philippines. The start has been good. Our first day is done, we resume our meeting tomorrow because whatever we agree on now, we can't sign it yet because we are not yet in a position to. So once we're in a position to, and upon instructions of president-elect Rodrigo Duterte, it will be easier for us to proceed with the next steps to restore peace in the Philippines," Dureza said in an interview.

Sison told AP "there are no red flags yet" in the initial meeting.

"We were engaged in some kind of opening moves, in what you might call a chess game," he said.

SISON HOMECOMING

Sison also told ABS-CBN News that he is consulting his lawyers regarding possible legal complications in his planned return to the Philippines, following a recent statement of the U.S. government designating the communist New People’s Army (NPA) as a terrorist organization.

Agcaoili earlier said Sison's return from his exile in The Netherlands is "now a ticklish issue." He explained there is no direct flight between Holland and Manila, so Sison could be arrested in transit points.

ABS-CBN News also learned that Sison may lose his refugee or asylum-seeker status in Norway if he returns even temporarily to the Philippines. Sison was given refugee status based on the European Convention on Human Rights because of the supposed threat of persecution against him in the Philippines.

But Sison, who has been in exile since 1987, said there is no rush in his planned homecoming. "Kinokonsulta ko naman ang mga abogado."

"Wala naman pagmamadali, walang pagmamadali."

READ: Joma Sison hopes to end exile under Duterte

Meanwhile, Dureza assured Sison the Duterte administration is prepared to aid him.

"Since he is already a very strong partner in finding a sustainable solution here, we would like also to commit to him na tutulong din kami in whatever way," he said.

Sison was Duterte's teacher at the Lyceum University in the 1960s. He has also vowed to help speed up negotiations to end Asia's longest running insurgency.

SHARED OPTIMISM

In a Facebook post past noon on Wednesday, Dureza said there is "evident shared optimism" on both sides because of Duterte's declaration to seek an "early sustainable peace for the nation."

"Both sides agreed that since the government participants have not yet assumed office, the consensus points, if any, will be initialed for authentication purposes at the close of the informal talks and to be formalized soon after President-elect Duterte's government has assumed office," said Dureza.

Peace talks hit a snag in 2013 after incumbent President Benigno Aquino III rejected the communists' demand for the release of their jailed comrades.