The Philippines opened a coast guard base on the contested island of Thitu on Friday, fully equipped to monitor passing vessels in the South China Sea.

Manila says the base will monitor the behavior of Chinese ships and aircraft in the waterway, accusing Beijing of seeking to bully it over the Spratly archipelago.

Why does the Philippines say it needs a base?

Earlier this year, the Philippine Coast Guard said it had spotted a Chinese navy ship and dozens of militia vessels near the island, which is Manila's main strategic outpost in the South China Sea.

Staff at the three-story facility will use radar, satellite communication, and cameras to observe the surrounding waters.

Confrontations between Chinese and Philippine ships have intensified this year with fears that such standoffs could lead to a larger conflict. In October, Beijing and Manila traded blame over two collisions near the Second Thomas Shoal, part of the Spratly archipelago.

"The behavior of the Chinese Coast Guard, People's Liberation Army (PLA) Navy and Chinese militias are sometimes unpredictable," Eduardo Ano, the Philippine national security adviser, said while visiting the island for the inauguration.

"They do not adhere to the international order, to the rule of law," he told reporters.

Ano said Chinese vessels had engaged in "illegal" and "aggressive" behavior towards Filipino fishermen and patrol boats.

"These systems will greatly enhance the PCG's ability to monitor the movements of the Chinese maritime forces, other countries that might be coming here, and also as well as our own public vessels and aircraft," he added.

What's important about the island?

Thitu, locally known as Pag-asa, lies about 300 miles (480 kilometers) west of the Philippine province of Palawan and is home to some 200 people. Manila uses it to maintain its territorial claim to the surrounding area.

China claims most of the South China Sea, including some islands and waters near the shores of its neighbors and far from the Chinese mainland. It has built artificial islands and military bases in the area to reinforce its stance.

Alongside the Philippines and China, other countries with rival claims to parts of the maritime area include Brunei, Malaysia, Taiwan and Vietnam.

The busy waterway is a conduit for goods in excess of $3 trillion (some €2.75 trillion) every year.

rc/nm (AFP, AP Reuters)