Philippine President Rodrigo Duterte’s agreement to give a U.S. military pact its second chance despite distaste for Washington shows his relations with China are chafing after four years, analysts believe.Duterte’s foreign secretary announced June 3 that the Philippines would extend a Visiting Forces Agreement with the United States at least until late 2020. The government said in February it would end the 21-year-old pact that lets American troops freely access the Philippines for joint exercises. Washington sees the Southeast Asian archipelago as a strategic spot in case of any conflict in East Asia.Foreign Secretary Teodoro Locsin told a news conference last week that “heightened superpower tensions” in Asia motivated his government to retain the agreement.Role of South China SeaChina, which has Asia’s biggest military and a maritime sovereignty dispute with the Philippines, grew as a threat in the first half of the year, scholars in the region say. Beijing let a fishing fleet sail near a Philippine-occupied South China Sea islet, sent a survey vessel to a part of the same sea claimed by Malaysia and prompted the U.S. Navy to carry out four “freedom of navigation operations.”“All contributed to the perception that it’s not a good time to be letting down the guard, so to speak,” said Jay Batongbacal, international maritime affairs professor at University of the Philippines.China claims about 90 percent of the sea, overlapping parts of a Philippine exclusive economic zone. The U.S. government, a former Philippine colonizer, says the South China Sea should stay open internationally. Manila and Washington also abide by a mutual defense treaty. More than 100 Chinese vessels had surrounded Philippine-held islets last year. In 2012 navy ships from the two countries got locked in a standoff over fishery-rich Scarborough Shoal.Duterte surprised world leaders and his own citizens in 2016 by laying aside the maritime sovereignty dispute to pursue a new friendship with China. China reciprocated with pledges of billions of dollars in aid and investment, including 150,000 COVID-19 testing kits and 70,000 N95 facemasks offered last month.The Philippine president has railed against U.S. influence in his country. He resented U.S. criticism of the deadly Philippine anti-drug campaign under ex-president Barack Obama and the revocation in January of a U.S. visa for former Philippine police chief Ronald Dela Rosa. Dela Rosa, now a senator, was key to the drug campaign marked by extrajudicial killings.But Duterte trusts the U.S. military over China’s armed forces, said Alexander Huang, strategic studies professor at Tamkang University in Taiwan. Ordinary Filipinos as well as senior military personnel prefer the United States to China as an ally.“To the very basic Philippine interest, they will not give the People’s Liberation Army access to their facilities,” Huang said. “And the United States would not allow that.”COVID-19 a factorIn the event of a conflict, Philippine troops would need backup especially now as they help the national police handle COVID-19, Batongbacal said. U.S. troops could enter the Philippines only with special permission if the visiting forces agreement ended.The Philippines may have extended the agreement as a negotiating tool, said Stephen Nagy, a senior associate professor of politics and international studies at International Christian University in Tokyo.Duterte may ask visiting U.S. troops to offer more training or bring certain assets, he said. Former U.S. Cold War foe China may step in with more help too as a counterweight, he said.“Maybe this reversal is just a way of trying to get a few more concessions out of the United States, or maybe they really are worried about China,” said Derek Grossman, senior defense analyst with the RAND Corp. research institution in the United States.