Philippines Senate President Vicente “Tito” Sotto III shocked the nation Thursday by coming out in defense of granting China fishing rights in Philippine sovereign waters in light of a Chinese ship sinking a Filipino fishing vessel and refusing to rescue its crew this month.

Sotto argued that there was no way to confirm that the fish being caught had not swam from China into Philippine territory, so China should be allowed to catch them.

The Philippine constitution bans the government from allowing any other country to fish in Philippine sovereign maritime territory, the news outlet Rappler noted this week.

President Rodrigo Duterte has refused to challenge China as the Communist Party expands its presence in the South China Sea, disregarding establishing international law that makes Chinese claims to the region illegal. In the past 24 hours, Duterte has vacillated on the issue of permitting Chinese ships to fish near Recto Bank, where they sank the Philippine fishing ship, and in doing so invited threats of impeachment.

Sotto defended Duterte’s inclination to allow the fishing by arguing that the fish in question may have been born in Chinese waters.

“It’s very difficult to say that there’s exclusivity when it’s underwater,” he told Early Edition, a program on Philippine broadcaster ANC. “The fish could be coming from China, and the fish from the Philippines could be going to China if we want to be technical about it and relate it to the constitutionality of what should be owned by us.”

“There are exclusive type of fish that are only found in China but can be found here because of migration,” he added, without clarifying how a fish that is found in both countries is “exclusive” only to China.

The Philippine Star adds that Sotto did not oppose an impeachment process against Duterte, instead saying that beginning impeachment proceedings “would be a very good test case” for the constitutionality of the president’s proposal.

China claims much of the West Philippine Sea, the subsection of the South China Sea where the fishing ship sank. Beijing alleges that sovereign maritime territory belonging to the Philippines, Vietnam, Malaysia, Taiwan, and Brunei has all been Chinese “since ancient times.” The Permanent Court of Arbitration at the Hague found China’s claims invalid under the U.N. Convention on the Law of the Sea (UNCLOS), but China has ignored the ruling and the plaintiff in the case, the Philippines, has refused to enforce it.

The latest incident stemming from this was the sinking of a fishing ship in early June after a Chinese ship, illegally present in Philippine waters, rammed it and fled. The 22 crew members were left to die, saved by a friendly Vietnamese ship that found them hours later. The Duterte administration’s response to the sinking was initially a fierce one, before Duterte himself weighed in.

“We will not allow ourselves to be assaulted, to be bullied, to be the subject of such barbaric, uncivilised and outrageous actions from any source,” spokesman Salvador Panelo initially told reporters.

Lieutenant Colonel Stephen Penetrante, a spokesman for the armed forces, said that the sinking was “far from accidental,” an assertion Duterte later publicly doubted.

In response, Philippine protesters congregated in Manila to burn Chinese flags and call for a total blocking of the Chinese government from Philippine sovereign territory. Since those protests, Duterte has publicly refuted that the sinking was accidentally and, on Wednesday, asserted that he would not block Chinese ships from Philippine waters.

“We cannot drive them away because they have insisted it’s theirs,” Duterte said, adding that “of course” he would allow the Chinese to fish in Philippine waters.

Panelo, who initially called the sinking “barbaric,” rapidly changed his tune.

“He [Duterte] does not want to force them to take a risk-taking measure, the Filipinos insist on danger,” Panelo said on Thursday. “The President said, ‘I have been saying so long ago, that the critics want to pursue an aggressive, isolationist policy that is very dangerous today.'”

Rappler noted following Duterte’s remarks that his position, while legal under UNCLOS – which lets nations administer their sovereign waters however they want – is unconstitutional. The outlet quoted the constitution’s Article 12, which reads: “The State shall protect the nation’s marine wealth in its archipelagic waters, territorial sea, and exclusive economic zone, and reserve its use and enjoyment exclusively to Filipino citizens.”

“I have evaluated that it appears that what the President meant was China would not allow their nationals from fishing in our EEZ since they treat us as their friends, knowing that permitting their fishermen to fish in our EEZ would only result in an unwanted hostility leading to an armed confrontation,” Panelo attempted to clarify on Thursday. “The president will not relinquish our sovereign rights over our country’s exclusive economic zone [EEZ].”

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