A U.S. aircraft carrier group led by the USS Theodore Roosevelt entered the South China Sea this past weekend to promote "freedom of the seas," the U.S. military said Sunday.

The group entered the South China Sea as Taiwan reported an incursion of bombers and fighter jets from China into its air defense identification zone near the Pratas Islands.

Eight bombers and four fighter jets entered the zone and Taiwan's air force deployed missiles to "monitor" the incursion, the island's defense ministry said. The U.S. State Department encouraged China to stop pressuring Taiwan.

Li Haidong, a professor at the Institute of International Relations of China Foreign Affairs University in Beijing, Sunday told the Global Times the sailing of the carrier group showed the U.S. is not giving up its continued interference in China's internal affairs over the Taiwan question.

By hyping the "China military threat theory," the U.S. statement twisted the truth and attempted to cover the bullying essence of US diplomacy, experts told Global Times.

The U.S. statement said its commitment to Taiwan was "rock-solid," the State Department said and warned China's "attempts to intimidate" the island were a threat to regional peace.

Department representative Ned Price said it was concerned at a "pattern of ongoing China attempts to intimidate its neighbors, including Taiwan" and "urges Beijing to cease its military, diplomatic and economic pressure against Taiwan."

It asked China to talk with Taiwan and halt military pressure on the island.

The Chinese flights were among the most significant in a campaign that has seen almost daily incursions into the airspace around Taiwan.

"We will stand with friends and allies to advance our shared prosperity, security and values in the Indo-Pacific region - and that includes deepening our ties with democratic Taiwan," the department said in the statement.

Meanwhile, China said over the weekend the flights were "routine operations."

Military analysts said the flights were aimed at the U.S. carrier group and used the warship as a simulated target in an exercise. Others said the China exercises were routine and not necessarily related to the U.S. operations, according to Reuters.

A mainland military expert who asked for anonymity told the Global Times Sunday that China's operations were not necessarily related to the U.S. aircraft carrier group's arrival to the South China Sea because both countries were conducting scheduled exercises.