HAINAN — The Duterte administration is hopeful that the Philippines' joint oil and gas exploration agreement with China will be finished within the "next couple of months" as it stressed that any deal should be compliant with existing laws.

Philippine Ambassador to China Chito Sta. Romana said a joint exploration deal would not be signed during President Rodrigo Duterte's visit here as the two countries are still ironing out details.

"I think the best estimate I have gotten is from (Foreign Affairs) Secretary (Alan) Cayetano that we are trying to see if we can achieve an agreement, hopefully, within the next couple of months but, as always, in negotiations, we can never predict. If it's necesary to take a longer time. We will take our time as long as we meet our objectives," Sta. Romana told journalists on Monday.

"But if we can do it, and there is political willingness on both sides, (we will) try to achieve an agreement as soon as possible. But it won't be tomorrow," he added.

The Philippines and China agreed in February to create a special panel that would craft a framework on how they can jointly explore oil and gas in the South China Sea, the subject of a longstanding maritime row between the two countries and four other claimants.

Critics have accused Duterte of abandoning the Philippines' claims in the South China Sea but officials insist the proposed exploration has a precedent, namely the 2005 Joint Seismic Marine Undertaking (JMSU) between the Philippines, China, and Vietnam.

The legality of the agreement, which was signed during the time of former president Gloria Macapagal-Arroyo, was questioned before the Supreme Court in 2008. Former lawmakers have asked the Supreme Court to act on the petition to void the JMSU in 2014 but the court has yet to issue a ruling.

'Agreement must be acceptable to Philippines, China'

Sta. Romana stressed that a joint exploration agreement should be acceptable to both the Philippines and China.

"The Philippines is aware of certain parameters. It has be within our constitutional requirements, and legal requirements. The Chinese have their own parameters but there is political will from both sides to move forward...We know, it has to stand public scrutiny. It has to be acceptable to the Filipino people," the envoy said.

"The basic point we are trying to achieve is to be able to find a way to enhance our energy security, to solve our crying need for energy in a way we can achieve it with a peaceful diplomatic solution so we can finally explore and develop the resources that belong to us and avoid making it a source of conflict," he added.

Roque previously disclosed that two areas in Palawan are being eyed as possible sites for the joint exploration between the Philippines and China.

The two areas are within the Philippines' 200-nautical mile exclusive economic zone (EEZ). The Philippines has exclusive rights to exploit the natural resources in its EEZ.

Service Contract 57, a project located in Calamian in northwest Palawan, is not covered by a maritime dispute while Service Contract 72, which covers Recto (Reed) Bank, is also being claimed by China.

Service Contract 57 was awarded to the Philippine National Oil Co. - Exploration Corp. in 2005 and covers a total area of 7,120 square kilometers in offshore northwest Palawan.

Recto Bank, meanwhile, is located about 80 nautical miles west of southwestern Palawan province.

Exploration activities in Recto Bank were halted in 2014 after the Philippines under former president Benigno Aquino III challenged China's maritime claim of China in the West Philippine Sea, the area in the SOuth China Sea being claimed by Manila.

An arbitral court in Hague declared in 2016 that China's expansive claim has no legal basis but the Chinese government refused to recognize the ruling.

Duterte has agreed to set aside the ruling to improve the Philippines' relationship with China but promised to take up the issue with his Chinese counterpart before his term ends in 2022.