The one-day exercise was being carried out in the West Philippine Sea, Philippine air force spokesperson Maria Consuelo Castillo said, using Manila's term for waters in the South China Sea that fall within its exclusive economic zone, Reuters reported.
Castillo said the two Philippine FA-50 fighter aircrafts and two US B1-B bombers were taking part in the exercises, which will included flying over Scarborough Shoal, a disputed maritime feature in the South China Sea which China controls.
"This is not in relation to any particular issue. This is just part of the usual training we have," Castillo told a media briefing.
Security engagements between the two treaty allies have ramped up under President Ferdinand Marcos Jr., against a backdrop of rising tensions between Manila and Bejing due to their overlapping claims in the South China Sea.
At the briefing, the Philippine navy said it was "closely monitoring" three Chinese navy vessels within Manila's maritime zones, including a Jiangkai class guided missile frigate.
"The presence of PLA-N (People's Liberation Army-Navy) reflects the People's Republic of China's complete disregard for international law and undermines the peace and stability in the region," navy spokesperson John Percie Alcos said.
State news agency Xinhua reported on Monday the passage of the Chinese fleet was consistent with international law, quoting a spokesperson from the PLA's Southern Theater Command.