Duterte, however, said the Chinese leader would not back down on Beijing's territorial claim and justified his decision not to immediately demand Chinese compliance with a ruling by a United Nations -linked tribunal that invalidated China's sweeping claims in the South China Sea on historical grounds.
President Donald Trump has offered to mediate in the South China Sea disputes, while his Chinese counterpart played down concerns over Beijing's military build-up and the prospects of war in the contested waters.
"China's greatest hope is for peace and stability in the South China Sea", Li told ASEAN leaders in Manila.
Chinese Premier Li Keqiang takes a bow after the annual Asean-China summit, held Monday in Manila.
The draft framework was drawn up in May at the 14th Senior Officials' Meeting on the Implementation of the Declaration on the Conduct of Parties in the South China Sea in Guizhou, China.
"We believe that regional countries have the will, wisdom and capability to deal with the South China Sea issue in a proper way", Geng said, without directly mentioning Trump's offer.
Trump was in Manila on Monday for meetings with the 10-member Association of Southeast Asian Nations (ASEAN) and several other countries.
China in recent years has built artificial islands and increased its militarisation in the waters, drawing criticism from Washington, which argues that the United States has a national interest in freedom of navigation in sea lanes critical for world trade.
"Of course, the claimant countries have to answer as a group or individually, and not one country can just give an instant reply because mediation involves all of the claimants and non-claimants", he pointed out.
In a joint statement, Asean and China agreed to "intensify cooperation and assistance to combat corruption", as part of efforts to enhance regional cooperation under the Asean-China Strategic Partnership.
In 2013, the Philippines filed an global arbitration case against China, and scored victory three years later.
But the Philippines, after President Rodrigo Duterte took office past year, decided not to use the ruling to pressure China.
Unlike China, the U.S. is not a claimant to the potentially oil-rich and busy waters, but it has declared it has a national interest in ensuring freedom of navigation and overflight and the peaceful resolution of the disputes.
To mend the strained relations of the Philippines and China, Duterte, who came into power in 2016, made a decision to temporarily set aside the arbitration ruling. So we welcome that offer, let's see how everyone's response. Duterte hosted a gala dinner Sunday for leaders including Trump, Russian Prime Minister Dmitry Medvedev, Chinese Premier Li Keqiang and Japanese Prime Minister Shinzo Abe, who all wore traditional barong shirts.