Buoyed by exceptionally high approval ratings and a legislature dominated by his allies, Duterte used his annual State of the Nation address to urge action on a key unrealised plank of his tough-on-crime stance.

"I respectfully request congress to reinstate the death penalty for heinous crimes related to drugs as well as plunder," he said referring also to the nation's deep rooted corruption problem.

"My countrymen, it is a sad commentary that we cannot distinguish our need from our greed, our principles from prejudices," he told hundreds of assembled lawmakers, diplomats and celebrities in Manila.

Though his campaign is the subject of a recently launched review by the United Nations' rights body and preliminary inquiry from International Criminal Court (ICC) prosecutors, he was defiant in his address.

"Duterte -- extrajudicial killing -- report to the ICC," he said. "If you can provide me with a good comfortable cell, heated during winter time... unlimited conjugal visits, we can understand each other."

In May's mid-term elections Duterte allies won control of the Senate, which had stopped cold some of his most controversial proposals, including bringing back capital punishment.

However, his allies, including the daughter of deceased former dictator Ferdinand Marcos and the first head of Duterte's drug war, have said they would back the death penalty.

Just as he began his 90-minute address he pointed to the popular support that underpins his brash rule, which faces censure for locking up detractors and attacking critical journalists.

"The latest survey results shows that my disapproval rating is 3 percent," he said to applause. It "inspires me with determination to pursue relentlessly what we have started."

Yet, Duterte's embrace of China is a weak spot among segments of the Philippine public and he devoted a long section of his speech to defending his stance.

The sinking last month of a Philippine fishing vessel by a Chinese boat in the disputed South China Sea stoked simmering anger over the issue.

Duterte set aside the once tense standoff over Beijing's extensive claims to the resource-rich waterway to court investment, but he faces accusations of trading away Philippine sovereignty.

"China also claims the property and he is in possession. That is the problem," the president said. "We are claiming the same but we are not in possession."

"I will send my marines there and drive away Chinese fishermen, I guarantee you not one of them will come alive," he added.

His comments drew immediate rebukes from opposition lawmaker Risa Hontiveros.

"It appeared like it was not a Philippine president speaking but a representative of China," she wrote on Twitter.