Canberra: President Ferdinand Marcos told Australia's parliament his country was on the "frontline" of a battle for regional peace Thursday -- pledging resolve as he sought support in maritime disputes with China.

With Beijing's warships detected in waters off his country's coast, Marcos told Australian lawmakers that "the Philippines now finds itself on the frontline against actions that undermine regional peace, erode regional stability, and threaten regional success."

He vowed to remain firm in defending his country's sovereignty.

"I will not allow any attempt by any foreign power to take even one square inch of our sovereign territory," Marcos said to loud applause.

"The challenges that we face may be formidable, but equally formidable is our resolve. We will not yield."

He called on Australia and other partners to join forces to address the threats to the rule of law, stability, and peace.

"We are called upon once again to join forces, together with other partners, in the face of threats to the rule of law, to stability, and to peace," he added.

Marcos said that Australia plays a crucial role, being one of only two countries with which the Philippines has a Visiting Forces Agreement.

"Once again, we must come together as partners to face the common challenges confronting the region. Not one single country can do this by itself. No single force alone can counter them by themselves," Marcos said.

"We must reinforce each other's strengths. We must protect the peace that we fought for during the war and have jealously guarded in the decades since. We must oppose actions that clearly denigrate the rule of law," he added.

Philippine officials earlier said they detected Chinese navy vessels around the Scarborough Shoal -- an area seized by Beijing in 2012.

Marcos has called the deployment of warships a new and "worrisome" development.