In a Chairman's Statement released Sunday, ASEAN leaders said the completion of framework will facilitate the early conclusion of an "effective COC".
Nevertheless, they noted concerns expressed by some leaders over recent developments in the area.
Duterte has said he is "happy to slaughter" millions of addicts in his quest to stop the Philippines from becoming a narco-state. China has refused to recognize the ruling and insisted that it would not affect its sovereign rights in the South China Sea.
Duterte, who has loosened the Philippines' long alliance with the United States while strengthening ties with China and Russian Federation, said he could not commit to the American president because of a busy schedule that included a trip to Moscow.
Meanwhile, Armed Forces Chief of Staff General Eduardo Año said the military is also open to holding joint exercises with other countries. However, it did include in a section, separate to the South China Sea chapter, about the need to show "full respect for legal and diplomatic processes" in resolving disputes.
The chairman's statement issued on Sunday made no mention to the arbitration case.
A foreign diplomat based in Manila told the AP that the Philippines circulated a stronger draft statement to other ASEAN member states, which was backed by countries like Vietnam.
Diplomatic sources said Chinese embassy officials in Manila had lobbied intensely to remove the phrase in the final draft.
China, through its ambassador to Manila, had this week been campaigning to weaken it further, delegates and diplomats told AFP.
In addition, he said the issue of terrorism had also drew attention at the summit in which Malaysia said the country's contribution, including the radicalisation programme had achieved a high level of success.
It says they urged North Korea to "immediately comply" with all relevant U.N. Security Council resolutions and "stressed the importance of self-restraint in the interest of maintaining peace, security and stability in the region and the world".
It also indicates four ASEAN members who the diplomats said had wanted a firmer position had agreed to the more conciliatory tone in the statement.
"We are at our best level of friendship with China after I went there", the President of the Philippines said, referring to his previous visit to Beijing in October 2016. The group wants Beijing to sign a framework agreement for a code of conduct in the South China Sea, which would be a precursor to a long-delayed and supposedly legally binding pact governing behavior in the South China Sea to avoid conflict.
'It can not be an issue anymore. "It's already there. What will be the goal of discussing it if you can't do anything about it?" he said, referring to China's islands in the Spratlys.
The Philippines has claims that overlap with those of China in the South China Sea.
The United States has criticized the construction work, warning against militarization in the waterway where $5 trillion in annual trade passes.
ASEAN member states Brunei, Malaysia, the Philippines and Vietnam have claims that overlap those of China in the South China Sea through which much global commerce passes, and where marine resources, and potentially oil and gas deposits, are abundant.