Beijing says it is conducting military exercises near the Taiwan Strait, citing the need to safeguard its sovereignty and territorial integrity.
Earlier this week, the US Department of State announced that it would be sending a senior diplomat, Keith Krach, to attend the memorial service for former Taiwanese political leader Lee Teng-hui. Washington and Taiwan have reportedly been in negotiations to initiate an economic dialogue.
According to China's Ministry of Foreign Affairs (MOFA), the visit violates the one-China principle and the three China-US joint communiques.
On Wednesday, media also reported that the United States are planning to sell up to seven major weapons systems to Taiwan.
The US, along with the majority of other states, does not recognise Taiwan as an independent entity and sticks to the "One China" policy. However, it has managed to maintain informal relations with Taiwan, despite severing diplomatic ties with the island in 1979.