Washington: As hostilities between China and the Philippines in the South China Sea escalates, US President Joe Biden said that the US military is willing to fight nuclear-armed China on behalf of the Philippines after ships from the two Asian countries collided near a disputed unpopulated island in the South China Sea, New York Post reported.

"The United States defence agreement with the Philippines is ironclad. Any attack on the Filipino aircraft, vessels or armed forces will invoke our mutual defence treaty with the Philippines," Biden said during a joint press conference.

According to the 1951 mutual defence pact, the US and the Philippines will jointly "defend themselves against external armed attack."

Earlier on Sunday, two of Manila's military ships collided with a Chinese vessel that sought to block them from reaching the disputed Second Thomas Shoal, which is strategically located along important commercial shipping routes but also submerged at high tide, according to New York Post.

The Second Thomas Shoal is located much closer to the Philippines than to China and is one of dozens of islands in the South China Sea disputed by China and the governments of nearby countries including Vietnam, Malaysia, Brunei and Taiwan.

The Philippines summoned the Chinese ambassador on Monday about these two near collisions between Chinese and Filipino ships over the weekend in the disputed South China Sea, local media reported.

The Philippine Daily Inquirer reported today that the country's Department of Foreign Affairs (DFA) had summoned a Chinese envoy after Chinese vessels hit a resupply boat contracted by the Philippines armed forces and a Philippine coast guard ship in the Spratly Islands chain in the West Philippine Sea on October 22 morning.

Jonathan Malaya, a spokesperson for the Philippines National Security Council, told a press conference on Monday that one of the Philippines's boats was damaged in the incident.

China's move was "provocative, irresponsible and illegal" and "imperilled the safety of the crew" of the Philippine boats, the National Task Force for the West Philippine Sea said as reported by CNN.

Moreover, House Republicans initiated an impeachment inquiry last month into the president's role in his son Hunter Biden and brother James Biden's foreign business dealings, including a pair of ventures with Chinese government-linked companies that resulted in millions of dollars of income going to the Bidens.