The deal was announced on Friday, when the two countries issued a joint statement listing the bases as Antonio Bautista Air Base, close to the contested Spratly Islands in the South China Sea, Basa Air Base north of Manila, Fort Magsaysay in Palayan, Lumbia Air Base in Mindanao and Mactan-Benito Ebuen Air Base in Cebu.

According to US Deputy Assistant Secretary of Defense Amy Searight, the deal was inked under a 2014 Enhanced Defense Cooperation Agreement (EDCA) that allows the US to expand its military presence in its former colony through rotation of ships and aircraft.

Searight described the Manilla government as a "critical US ally," announcing US Defense Secretary Ash Carter’s visit to the East Asian country.

The agreement, in place for at least 10 years, is “pretty big,” US Ambassador to the Philippines Philip Goldberg told reporters.

It allows for enhancement of ties with Philippine and facilitates a greater military presence for Washington as part of the US rebalance to Asia.

However, he stressed that it did not provide for permanent US bases in the country, although such bases existed for 94 years until 1991, when the Philippine Senate voted to evict them.

"This isn't a return to that era. These are different reasons and for 21st century issues, including maritime security," he said, adding that no US deployments would be done without Philippine’s approval.

Washington is keen to boost military ties with East Asian countries, such as Taiwan and Singapore, and extend its own regional presence in the face of China's territorial claims in the South China Sea, one of the world's busiest trade routes through which passes more than $5 trillion.

In recent months, tensions have been rising between Washington and Beijing over the situation in the disputed waters, with the former accusing the latter of militarizing the sea.

The disputed waters are also claimed by countries such as Vietnam, Taiwan, the Philippines, Malaysia, and Brunei.

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