Security forces in the Philippines fired water cannon on Thursday to prevent hundreds of protesters from disrupting the Asia-Pacific Economic Cooperation (APEC) leaders' meeting in the capital, Manila.

Human rights and pro-labour groups rallied against the annual APEC summit, saying it works to benefit only multinationals and rich countries at the expense of developing economies.

"People here are calling themselves a 'coalition of people' standing against the 'coalition of oppressors'," reported Al Jazeera's Margas Ortiga. "They see trade groups such as APEC basically helping only big corporations. They say they are the ones who are meant to be helped."

APEC, which accounts for 60 percent of global output and nearly half of world trade, is aiming for a larger free-trade area for its 21-member states by 2025.

Regional tensions over the South China Sea and security concerns after the attack by Islamic State of Iraq and the Levant (ISIL) in Paris could eclipse efforts by Pacific-Rim leaders to boost trade and growth across a region of about three billion people.

APEC leaders called on Thursday for increased international cooperation in the fight against terrorism as they met on the last day of the meeting.

A copy of the declaration that the leaders will issue following their talks, seen by The Associated Press, strongly condemned "all acts, methods, and practices of terrorism".

Social activists have decried Manila's hosting of the annual summit, which was attended by US President Barack Obama, Chinese President Xi Jinping, and Japanese Prime Minister Shinzo Abe.

"They are expected to come up with some sort of draft to explain exactly how they intend to make their economies more inclusive, so that people who are on the streets will feel more included in the growth that APEC economies are striving for," Ortigas said.

Police in full riot gear clashed with protesters from the Bagong Alyansang Makabayan, a left-wing activist group, to keep them away from the Philippine International Convention Center - the site of the two-day summit.

Demonstrators chanted slogans such as "We will struggle" and "Junk APEC" while anti-riot police pushed the crowd back.

"These demonstrations will not stop, even if it means we have to go head-to-head against the entire police force and we have to break through all the barriers," Charisse Bernadine Banez, spokeswoman of the League of Filipino Students, told Reuters.

At least one policeman was injured, the Philippine National Police spokesperson Wilben Mayor told reporters. He appealed to protesters to halt the demonstrations, but said police would exercise maximum tolerance.

The activists have decried Manila's hosting of the annual summit [Lino Escandor II/AP]

Source: Al Jazeera and agencies