MANILA – Philippine President Rodrigo Duterte's incendiary remarks against US President Barack Obama earned cheers from various groups, but it also raised concerns that the controversial leader may be unnecessarily hurting Philippines' ties with its traditional ally.
READ: Duterte hits US anew before leaving for ASEAN Summit
Duterte was angered after learning that Obama was planning to discuss with him the human rights situation in the Philippines amid the tough-talking leader's bloody crackdown on illegal drugs.
He scoffed at the idea and uttered curses, saying such a move would be an interference to Philippine sovereignty.
Duterte's verbal insults prompted the White House to cancel what could have been the first meeting between Duterte and Obama during the Association of Southeast Asian Nations (ASEAN) Summit in Laos.
READ: Obama cancels meeting with Duterte after insult
Leftist groups, known for their disdain for the US, rejoiced over Duterte's treatment of the US leader.
Militant umbrella group Bagong Alyansang Makabayan (Bayan) lauded Duterte's statement, saying ''for the first time in forever, a Philippine president has the backbone to reject US intervention."
Bayan, however, said Duterte's words are not enough. It said this policy should lead the Philippines to terminate its ''unequal'' agreements with the US, such as the Visiting Forces Agreement (VFA) and the Enhanced Defense Cooperation Committee (EDCA).
The EDCA, which allows for the increased US military presence in the Philippines, was signed by the US and Philippines amid the latter's dispute with China over the West Philippine Sea.
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''Duterte can promote our interests in the West Philippine Sea vs China without having to rely on the US, who is only after its own agenda,'' Bayan said.
While slamming the US from time to time over a range of issues -- from its role as a Philippine colonizer and its inability to quell racial tensions among its citizens -- Duterte has sought closer ties with China.
While some appreciate Duterte's tough stance against the supposed US intervention, some observers say the firebrand is straining ties with its oldest and most powerful ally at a time Philippines needs help in dealing with a muscle-flexing China.
READ: PH worried, says more Chinese boats spotted at disputed shoal
Senator Antonio Trillanes IV, a staunch Duterte critic, said Duterte's attack on Obama was ''wrong on so many levels and will definitely have detrimental effects on our diplomatic relationship and alliance with the US."
''You don't just slap the face of the most powerful country in the world and expect to get away with it."
Trillanes added, the Philippines' security sector could be weakened because of the controversy.
Militant lawyer-turned-lawmaker Harry Roque said he also lauds Duterte for pursuing an independent foreign policy, but he is concerned that his ''undiplomatic language may unnecessarily cause diplomatic wrinkles."
''An independent foreign policy need not result in the disturbance of friendly relations with our traditional allies. To achieve this, tact, not firebrand rhetoric, is key,'' Roque said.
Roque added, despite Duterte's perceived US intervention on Philippine affairs, ''all countries and their leaders are still accountable to establish human rights conventions and institutions."
''Being asked about extralegal killings must be welcomed if we are to take the path of stopping the environment of impunity now prevailing,'' he said.
Former Philippine envoy to the United Nations Lauro Baja said the incident ''should not have happened as it sends the wrong signal to the two sides,'' but he is confident this incident is only a "blip'' in the two countries' ties.
''I hope it would not have a damaging effect. I think the positions in the West Philippine Sea are expounded already. If at all, it will only constitute a blip in the relations between US and the Philippines,'' he said.
''We should not worry too much about the consolation or lose too much sleep about it. This happens even between the closest allies. We should move on. It's good if there's an attempt to reschedule the meeting but that should be it."
Baja added, the ties between the two countries are bigger than the spat.
''US relations will outlive Obama and Duterte. It should. It endured in the last 50 years,'' he said.