MANILA- The Philippines will not allow itself to be bullied by any country, Malacañang assured Filipinos Thursday following the "collision" of a Chinese vessel and Filipino fishing boat in the disputed West Philippine Sea off Palawan.

Presidential Spokesperson Salvador Panelo insisted that Manila would not let its sovereignty be "thrashed upon" by any country as it sought an explanation from Beijing over the collision last Sunday.

"We will not allow ourselves to be assaulted, to be bullied, to be the subject of such barbaric, uncivilized and outrageous actions from any source," Panelo said during a Palace press briefing.

"Whether it's a form of bullying or not, it's outrageous, it's barbaric, it's uncivilized and we're condemning it," he said.

Twenty-two Filipino fishermen were left at sea off Recto (Reed) Bank by a Chinese crew in the West Philippine Sea Sunday in what the Philippine military likened to a "hit-and-run." They were rescued by a Vietnamese vessel.

The West Philippine Sea is the country's exclusive economic zone in the South China Sea.

President Rodrigo Duterte was "outraged" over the incident, Panelo said.

The Philippines has filed a diplomatic protest over the incident, Foreign Affairs Secretary Teodoro Locsin Jr. announced on social media Thursday.

• Philippines asks China to sanction ship crew in 'hit-and-run'

Tensions between Manila and Beijing have risen over the past few months amid the reported increase of Chinese vessels in the disputed South China Sea.

The Philippine military had said it monitored more than 600 Chinese ships near Pag-asa (Thitu) Island since January this year.

Satellite images taken in 2018 released earlier this year, meanwhile, showed that Chinese fishing vessels account for the largest number of ships operating in the Kalayaan Island Group (Spratlys) in the West Philippine Sea.

Beijing has refused to recognize a United Nations-backed arbitral ruling on a Philippine case which invalidated its sweeping claims in the South China Sea.

The ruling was handed down at the start of the term of Duterte, who has refused to flaunt Manila's victory in exchange for closer ties with Asia's largest economy.