BBC's John McLean: Manila will tackle the problem in the way it has always tackled it

Manila is determined to halt what it considers Chinese expansion in the Spratly Islands, a potentially lucrative and strategically important group of atolls and reefs.

Concern is growing in the Philippines about China's intentions after building work was started on the aptly named Mischief Reef.

China says it is constructing a shelter for fishermen. Manila says the site is a military installation and that it represents a military encroachment of its territory.

Mischief Reef: Disputed construction work

Philippine President Joseph Estrada's National Security Council has met for the first time since he took office last year to discuss the issue.

They agreed the battle with China should continue to be fought on two diplomatic fronts - through dialogue with China and with international help.

In seeking a solution, Mr Estrada took advice from former presidents Corazon Acquino and Fidel Ramos.

The council identified the Spratly dispute as one of its two "most urgent security concerns" - the other being attacks by Muslim separatist rebels in the southern island of Mindanao.

Islands divided

Six countries have some claim, in whole or in part, to the Spratly islands.

Some are so small there is barely enough room for one person to stand on dry land at high tide.

But because they are dispersed so widely across thousands of kilometres of the South China Sea they command control of strategically important sea lanes and access to rich fishing grounds.

It is also believed that they lie above massive reserves of oil and natural gas, though estimates of their potential value vary considerably.