Manila –

The Philippines' foreign ministry said on Wednesday it summoned China's ambassador to protest Beijing's drawing of baselines around the disputed Scarborough Shoal in the South China Sea.

"The said baselines infringe upon Philippine sovereignty and contravene international law," the ministry said in a statement.

The move follows China's definition on Sunday of the baseline for "territorial waters" around the shoal, which Beijing claims as Huangyan Island. The shoal is a key point of contention over sovereignty and fishing rights.

In response, China's ambassador Huang Xilian to the Philippines said late on Wednesday the baseline was a "necessary response" to the Philippines' new maritime law and a "routine measure" to strengthen maritime management, according to a statement from its embassy in the Philippines.

Philippine President Ferdinand Marcos Jr. last week signed the Maritime Zones Act and the Archipelagic Sea Lanes Act into law to strengthen the country's maritime claims and bolster its territorial integrity.

China had summoned the Philippines' ambassador to make "solemn representations" shortly after the acts were signed.

Huang reiterated China's objections to the new laws, warning that China would take necessary measures to protect its territorial sovereignty and maritime rights.

"We urge the Philippines to immediately cease any unilateral actions that could escalate disputes and complicate the situation, and to maintain peace and stability in the South China Sea," the embassy statement said.

Tensions between China and the Philippines over the South China Sea have escalated throughout the year, particularly over the Scarborough Shoal.

China claims nearly the entire South China Sea, a vital waterway for more than $3 trillion of annual ship-borne commerce, parts of which are also claimed by Brunei, Indonesia, Malaysia, the Philippines, and Vietnam.