MANILA — President Rodrigo Duterte on Wednesday threatened to execute "by hanging" a former foreign affairs secretary who had urged him to stand up to Chinese aggression in the West Philippine Sea.

Duterte alleged the Philippines lost Scarborough Shoal when former foreign affairs secretary Albert Del Rosario removed Philippine vessels from the area, during a standoff with Chinese ships in 2012.

"Ikaw Alberto, bakit mo pinaatras? Kaninong permission ka naghingi? Ngayon kung wala kang maibigay, p***** i** mo, 'wag mong ibigay sa akin ang kasalanan mo," the President said in a taped speech.

(You Alberto, why did you make them retreat? Whose permission did you ask? Now, if you can't give any son of a b****, don't pass your sin to me.)

"One day you will be tasked to answer for that, iyang pag-order dapat imbestigahan ka. I don’t know what will be the history of this country because if I were a leader anymore, I will execute you by hanging."

(One day you will be tasked to answer for that, you should be investigated.)

Del Rosario has said that the US brokered a deal to end the 2012 standoff hby having both China and the Philippines withdraw their ships.

However, Beijing "deceitfully breached our agreement by not withdrawing their 30 or more ships," he said.

• Duterte told about China's control of Scarborough Shoal; Beijing breached pull-out deal

Under the previous administration of former President Benigno Aquino, Del Rosario pursued an arbitral case against China. A United Nations-backed court in 2016 ruled in favor of Manila and junked Beijing's claim to about 90 percent of the South China Sea, within which is the smaller West Philippine Sea.

China refuses to obey the ruling.

Duterte "unfortunately" set aside the ruling in exchange of up to $24 billion pledge in Chinese investments and aid, Del Rosario and retired Supreme Court Senior Associate Justice Antonio said.

"Hindi naman ako humingi, offered ‘yan… I never asked anything, I was asking friendship, that was all," said Duterte.

(I never asked, it was offered.)

"Kung ako'y nagsisinungaling, mag-resign ako bukas kaagad."

(If I am lying, I will resign immediately tomorrow.)

China-controlled Scarborough is one of the region's richest fishing grounds and a flashpoint between the two countries, which have rival claims.

Manila and Beijing's spat flared again in March after hundreds of Chinese boats were spotted inside the Philippines' Exclusive Economic Zone.

• Philippines rejects Chinese fishing ban in West Philippine Sea

Once-frosty ties between the two countries had warmed under Duterte, who set aside the ruling in exchange for promises of trade and investment that critics say have largely not materialized.

Facing growing domestic pressure to take a harder line, Duterte said last week the Philippine maritime patrols would continue, insisting its sovereignty over the waters was not negotiable.

• Carpio, Del Rosario hit back at Duterte tirades over West Philippine Sea
• Palace: Duterte 'clear' he had no vow to take back West Philippine Sea
• Duterte: Philippines grateful to China, but West Philippine Sea 'cannot be bargained'

– With a report from Agence France-Presse

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