The Philippines is prepared to respond to China's attempts to disrupt its supply missions in the South China Sea and protect its troops stationed in the waterway, a top security official said on Wednesday.

Philippine Coast Guard personnel prepare rubber fenders after Chinese Coast Guard vessels blocked their way to a resupply mission at the Second Thomas Shoal in the South China.

Jonathan Malaya, the spokesperson of the National Security Council, said the Philippines is committed to maintaining its position at the Second Thomas Shoal and there will be no let up in re-supply missions to Filipino soldiers on a grounded warship there.

"Our commitment to maintain BRP Sierra Madre will always be there, so any attempt by China to interfere with re-supply missions will be met by the Philippines in a fashion that protects our troops," Malaya told a maritime forum.

Malaya reiterated that the counter-measures announced by Philippine President Ferdinand Marcos Jr last week against "aggressive" actions by China's coastguard will be "multi-dimensional" and not solely military in nature.

Part of these measures includes making "changes and adjustments" to Philippine re-supply missions and operations in the South China Sea, Malaya said without elaborating, citing security concerns.

Echoing an earlier call by the Philippine defence minister for the public not to fall victim to Chinese propaganda, Malaya warned of "foreign malign influence" meant to weaken the Philippines.

"We have seen that they are working here through their surrogates or if we may call them amplifiers, because there are definitely Chinese narratives which run counter to the truth," Malaya said.

The Philippines and China have had a series of maritime run-ins, including water cannon use, and heated verbal exchanges that has triggered concern about an escalation at sea.

China claims almost the entire South China Sea as its territory, policed by an armada of coastguard vessels, some more than 1,000 km (620 miles) from its mainland. China has maintained its responses have been appropriate in the face of Philippine encroachment.

In 2016, the Permanent Court of Arbitration in the Hague said China's claims in the South China Sea had no legal basis, a decision Beijing has rejected.

The row comes at a time when the Philippines and United States are deepening military ties, frustrating China, which sees Washington as interfering in its back yard.

"The root cause of the current escalation of maritime disputes between China and the Philippines is that the Philippines relied on the support of external forces, violated its commitments, and repeatedly engaged in provocations," Chinese foreign ministry spokesperson Wang Wenbin said at a regular briefing on Wednesday.

Wang urged the Philippines to "return to the correct path of properly managing disputes through dialogue and consultation as soon as possible."

Next week, Marcos will meet his American and Japanese counterparts at a trilateral summit in Washington, and Malaya said a "big aspect" of their discussions will be on security.

Philippines preparing for ‘worst case scenario’ in South China Sea

The Philippines said its navy was preparing for the “worst-case scenario” in the South China Sea to counter China amid growing military tensions in the disputed waters.

A top official tasked with strengthening maritime security in the West Philippines Sea said troops on the east coast were “studying all options”. However, the government of Ferdinand Marcos Jr has been advised to keep the focus on diplomacy to resolve the conflict.

“We are ready for what they are going to do. The troops stationed at Sierra Madre are prepared for the worst-case scenario,” Vice-Admiral Alberto Carlos said. “We are studying all options. It’s unacceptable if we are going to stop the resupply mission.”

The BRP Sierra Madre is a grounded ship on the Second Thomas Shoal in the South China Sea that has been the site of a series of escalating confrontations. Philippines says it had a right to run resupply missions to troops on the grounded World Two-era vessel.

The Philippines deliberately grounded the ship on the shoal in 1999 to assert its sovereignty claim on the atoll. China claims sovereignty over most of the South China Sea, a claim that cuts into the exclusive economic zones (EEZ) of Vietnam, the Philippines, Malaysia, Brunei and Indonesia. The grounded Philippines transport ship at the shoal is about 190km (118 miles) off the Philippine island of Palawan.

The remarks by Mr Carlos came as president Marcos Jr’s National Security Council (NSC) emphasised the need to exhaust all diplomatic measures to resolve the escalating tensions with China.

Mr Marcos Jr last week said the Philippines would implement unspecified measures against "illegal, coercive, aggressive, and dangerous attacks" by the Chinese coast guard in the South China Sea.

"The proportionate, deliberate and reasonable response the president was talking about covered not only the aspect of strengthening military and defence capabilities with other allies ... but it also talks about exhausting diplomatic efforts to resolve the issue," NSC spokesperson Jonathan Malaya said on state TV, describing the measures as multi-dimensional.

Mr Marcos Jr has ordered his government to strengthen the country’s coordination on maritime security to confront "a range of serious challenges" to territorial integrity and peace, according to a copy of the directive released on Sunday.

Tensions have ratcheted up between the Philippines and China after their armies were involved in a series of run-ins in the past year with the latest incidents of clashes resulting in injuries to coast guards.

Analysts have raised an alarm over the military posturing, urging for diplomatic negotiations to prevent the situation from escalating into an open conflict.

The latest flare-up happened on 23 March when three Filipino Navy sailors were injured after Chinese coast guard personnel used a water cannon.

It was to allegedly disrupt a Philippine resupply mission to the Second Thomas Shoal for soldiers guarding the BRP Sierra Madre. China has been accused of blocking resupply missions to those troops amid deepening military ties between the US and the Philippines.

Vice Admiral Carlos told the South China Morning Post it will be “unacceptable” to halt the resupply mission to Sierra Madre.

On Tuesday, Eduardo M Año, the national security adviser of the Philippines, and his US counterpart Jake Sullivan held a phone call to discuss "coercive, aggressive and deceptive actions" by Beijing.

Mr Ano "expressed his appreciation for the United States’ continued assurances and reaffirmation of its ironclad commitment" to their alliance, according to a statement.