The United States aircraft carrier USS Nimitz continues to operate in the South China Sea, satellite imagery shows, as the Chinese navy expands its presence in the Pacific Ocean.

The Seventh Fleet—the largest of the U.S. Navy‘s forward-deployed fleets, with more than 50 vessels and 150 aircraft—delivers “combat-credible forces” in the western Pacific and Indian Oceans alongside the U.S.’s allies and partners, the Fleet said in a statement to Newsweek.

Newsweek has also contacted the Chinese Defense Ministry for comment by email.

Why It Matters

The Nimitz began its “regularly scheduled deployment” to the western Pacific Ocean in late March—likely its final overseas mission before decommissioning. After a brief transit in the Strait of Malacca, the nuclear-powered warship returned to the South China Sea in late May.

The U.S. aircraft carrier deployment in the South China Sea, where China‘s territorial claims overlap those of other regional countries, comes as the Chinese navy—the world’s largest by hull count—has two aircraft carriers operating simultaneously in the broader western Pacific.

What To Know

According to satellite imagery captured on Sunday and shared by open-source intelligence researcher @MT_Anderson on X, formerly Twitter, the Nimitz was spotted operating in the West Philippine Sea, about 167 miles northeast of the disputed Scarborough Shoal.

The maritime feature, under China’s control since 2012, lies about 138 miles west of Luzon Island in the northern Philippines. Manila uses the term “West Philippine Sea” to refer to the portion of the South China Sea that falls within its 230-mile-wide exclusive economic zone.

The most recently released official photos, taken on June 2, show the Nimitz underway in the South China Sea. The aircraft carrier’s deployment demonstrates the U.S. Navy’s unwavering commitment to a free and open Indo-Pacific, according to a photo caption.

Meanwhile, the second American aircraft carrier deployed in the western Pacific Ocean, USS George Washington, was spotted departing its home port at Yokosuka naval base near Tokyo, Japan‘s capital, on Tuesday, according to photos taken by a local ship spotter.

The George Washington returned to Yokosuka on June 4 following “routine operations” in nearby waters. The aircraft carrier and its naval aviators are preparing for their first patrol since returning to Japan—a U.S. ally—for a forward deployment almost eight months ago.

What People Are Saying

The U.S. Seventh Fleet said in a statement to Newsweek: “Every day the U.S. Pacific Fleet operates to protect the security, freedom, and prosperity for the United States and our allies and partners, reflecting our commitment to maintaining peace and stability in the region.”

The Seventh Fleet is one of two fleets—along with the Third Fleet—that report to the Pacific Fleet, whose command area extends from the Pacific Ocean to the Indian Ocean.

U.S. Navy Rear Admiral Maximilian Clark, the commander of the Nimitz Carrier Strike Group, said in April: “Operating forward as a strike group hones our ability to maintain persistent and capable forces at sea, always ready to provide our leaders with a broad spectrum of military capabilities to respond to any crisis or contingency.”

What Happens Next

It remains to be seen whether the Nimitz will depart the South China Sea for the Philippine Sea—located east of the Philippines—to conduct operations with the George Washington.