The U.S. military is poised to secure expanded access to key bases in the Philippines on the heels of a significant revamp of U.S. force posture in Japan — developments that reflect the allies' concern with an increasingly fraught security environment in the region and a desire to deepen alliances with the United States, according to U.S. and Philippine officials.

While negotiations are still ongoing, an announcement is expected as soon as this week when Defense Secretary Lloyd Austin meets in Manila with his counterpart, Carlito Galvez, acting secretary of National Defense, and then with President Ferdinand Marcos Jr.

The expansion involves access to Philippine military bases, likely including two on the northern island of Luzon — which, analysts said, could give U.S. forces a strategic position from which to mount operations in the event of a conflict in Taiwan or the South China Sea. They will also facilitate cooperation on a range of security concerns, including more rapid responses to natural disasters and climate-related events.

Extensive work has been done over the last few months in the Philippines to assess and evaluate various sites, and at least two of them have been pinned down, said a State Department official, who like other officials spoke on the condition of anonymity because they were not authorized to speak about the deliberations.

A Philippine defense official said an agreement for the additional sites had "more or less" been made but would be formalized when the two defense secretaries meet. Aides from the two offices were continuing to iron out key details in recent days, and at least two of the new sites are in Luzon, he said.

U.S. national security adviser Jake Sullivan discussed the matter with his counterpart Eduardo Año earlier this month as part of a White House effort to step up cooperation with Indo-Pacific allies, a U.S. official said.

The increased military cooperation with the United States "bodes well for our defense posture," said the Philippine official. But, he emphasized, the Philippines' push to bolster its security "is not aimed at any particular country."

Marcos "realizes the dynamics of the region at the moment and that the Philippines really needs to step up," said the official, adding that the president has been closely monitoring developments in the Taiwan Strait and in the West Philippine Sea. "We've already got incursions from multiple countries and the tensions are still expected to rise."

While expanded base access is alone not the security linchpin for the region, "it's a pretty big deal," said Gregory Poling, director of the Southeast Asia program at the Center for Strategic and International Studies. "This is significant not just in terms of what it means for a Taiwan or South China Sea contingency. This is a signal that the Philippines are all in on modernizing the alliance, and that they understand that a modern alliance means they have responsibilities, too."

The Philippines, once a U.S. territory, has been a treaty ally since 1951. It hosted a massive U.S. presence after the end of World War II, including the two of the largest American military facilities overseas — an arrangement that ended in 1991 when the Philippine Senate, asserting the country's sovereignty was being violated, forced the Americans to relinquish all U.S. bases to the Philippines.

The mutual defense arrangement was further stressed under the administration of former president Rodrigo Duterte, arguably the most pro-Beijing and anti-American president ever of the Philippines. Duterte threatened to end the Visiting Forces Agreement, which gave legal protections to U.S. military in the Philippines. But after Austin visited in the summer of 2021, and in the face of increasing Chinese aggression in Philippine waters, Duterte withdrew the threat.

The election of Marcos last year continued a warming trend — President Joe Biden was the first foreign leader to call to congratulate him. But the deepening of the alliance, officials say, is rooted in a recognition that the region is becoming a more dangerous place. In November, for instance, the Chinese Coast Guard forcibly seized Chinese rocket debris being towed by the Philippine Navy near one of the Philippine-held islands. In December, Chinese militia ships were spotted swarming in the West Philippine Sea. And just last week Chinese vessels drove Philippine fishermen away from one of the reefs at which the Philippines has exclusive fishing rights.

China is the Philippines' largest trading partner and the Marcos family has historical ties to China: Marcos visited China in 1974 with his father, then-president Ferdinand E. Marcos, and his mother, Imelda Marcos, and met Chairman Mao Zedong. Nonetheless, Marcos has made clear he sees the gathering threat. Asked at the Davos Economic Forum in January whether the South China Sea issue keeps him up at night, he responded, "It keeps you up at night. It keeps you up in the day. It keeps you up most of the time."

He also said that "in terms of cross-strait tensions, we are at the very front line," a reference to the fact that the Philippines' northernmost islands are only some 200 miles from Taiwan and the likeliest place that refugees would flee in a conflict.

Marcos said that "whenever these tensions increase," involving Chinese and American vessels, "we are watching as bystanders" and if something goes wrong, "we are going to suffer."

But, he noted, the connection between the United States and the Philippines has "remained strong," and that the only way to remain strong and relevant "is to evolve."

Marcos said, "We have security arrangements with the United States, and that has come to the forefront … because of the increased tensions in our part of the world."

Marcos made a trip to Beijing in early January in which, he said, he raised South China Sea concerns. Those include China's Navy and Coast Guard denying Filipino fishermen access to their traditional fishing grounds as well as the buildup of artificial islands in Philippine waters. Though he came away with more than a dozen agreements involving tourism, trade and e-commerce, his Davos remarks later in the month make clear the security issue prevails.

"The world has changed," he said. "Now we are living within the context of all of these other forces that are coming out, especially around the region, around South China Sea."

The United States currently has access to four air force bases and one army base in the Philippines under a 2014 Enhanced Defense Cooperation Agreement. EDCA allows the U.S. military to operate in agreed locations on a rotational basis. None of the five bases are in Luzon's north.

In November, Vice President Kamala Harris became the highest-ranking U.S. official to visit the Philippine province of Palawan, a thin but roughly 200 mile-long island abutting the contested South China Sea. At the time of her visit, a senior administration official noted that the two allies had identified new locations "to deepen our work together."

That work would extend to security cooperation exercises, combined training activities, and allow the United States to more rapidly provide humanitarian relief in natural disasters, the official said. EDCA also provides economic benefits, the official said, noting that the United States has invested more than $82 million in existing bases, with the majority of contracts supporting the projects going to Philippine companies.

The expected EDCA expansion will follow an announcement earlier this month that the U.S. Marine Corps will be revamping a unit in Okinawa to be better able to fight in austere, remote islands by 2025. Under the plan, a new Marine Littoral Regiment would be equipped with advanced capabilities, such as anti-ship missiles that could be fired at Chinese ships in the event of a Taiwan conflict.

For over a decade the Pentagon has sought to disperse its presence across the island chains of the Western Pacific to make it harder for China to concentrate its attacks on U.S. bases. But this also helps countries like the Philippines ensure that China does not charge right through their archipelago to attack Taiwan or Japan, said Michael J. Green, chief executive of the China Studies Center at the University of Sydney.

"The Philippines are not necessarily signing on to U.S. war plans per se," said Green, who handled Asia issues at the White House under President George W. Bush. "But it's a big step forward that will be encouraging to the United States and allies like Japan, and a signal to China of the costs of coercion."

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• Japan looks beyond US alliance for help to deter China military

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