0739 GMT January 23, 2020
In a brief statement, and without giving an exact geographical location, the ministry said that the People's Liberation Army had in "recent days" held the exercises, Reuters reported.
"These drills were routine arrangements in accordance with annual plans for the military," it said, without elaborating.
China's southeast coast is one of the country's most sensitive regions as it faces Taiwan across the narrow Taiwan Strait.
On Friday, China said it would impose sanctions on US firms involved in a deal to sell $2.2 billion worth of tanks, missiles and related equipment to Taiwan, saying it harmed China's sovereignty and national security.
That announcement came as Taiwan President Tsai Ing-wen was visiting New York on a transit stop to diplomatic allies in the Caribbean, a trip that has also infuriated Beijing, further straining Sino-US ties already affected by a bitter trade war.
With the US currently engaged in a trade war with China, relations between Taipei and Washington have warmed considerably.
Unlike the last three American presidents, who were wary of angering Beijing, Donald Trump has ramped up relations with Taiwan.
And although Washington switched diplomatic recognition from Taipei to Beijing in 1979, it has remained Taiwan's most powerful unofficial ally and biggest arms supplier.
Chinese Foreign Minister Wang Yi on Friday warned Washington "not to play with fire with the Taiwan question" during a visit to Hungary.
Separately, Geng told a press briefing Friday that the US should not provide a platform for "Taiwan independence separatist forces."
In a statement on Sunday, Taiwan's Presidential Office cited National Security Council Deputy Secretary General Tsai Ming-yen as saying President Tsai had spoken by telephone with US House Speaker Nancy Pelosi while she was in the United States and met with other senators and members of Congress, without naming them.
Tsai said Taiwan and the United States can both forge even closer ties, and also thanked the United States for "the importance it attaches to the security of the Taiwan Strait" and the recently announced arms sale, the statement said.