MANILA: A strong earthquake rattled the northern Philippines early Saturday, the United States Geological Survey said.

The 5.7-magnitude quake's epicentre was 30 kilometres (20 miles) south of the Batan Islands and some 225 kilometres north of the archipelago's largest island, Luzon, the USGS said.

The Pacific Tsunami Warning Center has not issued a tsunami advisory, and there was no immediate word of damages or injuries.

The quake struck at 6.40 am local time (2240 GMT on Friday) and at a depth of 10 kilometres, the USGS said.

The archipelago nation, made up of more than 7,000 islands, sits on the Pacific "Ring of Fire" where continental plates collide, causing frequent seismic and volcanic activity. - AFP/ac