The Pentagon and State Department have informally notified Congress of a potential $2 billion deal with Taiwan that includes the first-time sale of one of the U.S. Army’s top tanks, according to an official familiar with the proposal, drawing protests from China.

The deal would contain the M1A2 Abrams tank, and a resupply of anti-air and anti-armor weapons, the official familiar with the matter said. The notification of the government-to-government sale doesn’t include F-16 fighters, which are still under State Department and Pentagon review, the person said.

“We are severely concerned about the U.S.’s move,” Chinese Foreign Ministry spokesman Geng Shuang told reporters in Beijing on Thursday. “We are firmly against U.S. arms sales to Taiwan. We urge the U.S. to see the high sensitivity and severe harm of arms sales to Taiwan.”

The move comes amid tensions over stalled trade talks between China and the U.S. China sees Taiwan as an integral part of its territory that it must unify, by force if necessary.

The package includes 108 of the tanks built by General Dynamics Corp., as well as 1,240 TOW wire-guided anti-tank missiles, 409 shoulder-launched “fire-and-forget” Javelin anti-tank missiles and 250 Stinger shoulder-fired anti-aircraft missiles made famous by Afghan “freedom fighters” in their war against the Soviet Union.

The informal notification, reported earlier Wednesday by Reuters, will be followed by a formal and public notification to Congress that’s likely to be approved within the normal 30-day review process. Taiwan’s Ministry of National Defense confirmed the request for the arms purchase on Thursday.

In March, China vigorously protested the Trump administration’s tacit approval of Taiwan’s request to buy more than 60 F-16s built by Lockheed Martin Corp.

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