Salvadoran President Salvador Sanchez Ceren was due to meet his Chinese counterpart Xi Jinping in Beijing on Thursday, just months after the small Central American nation broke its diplomatic ties with Taiwan.

The state visit comes one day before that of the president of the Dominican Republic, whose country also switched allegiances from Taiwan to China this year.

El Salvador and the Dominican Republic are among a growing number of states who have left Taiwan behind in favor of resuming or establishing relations with China, which considers the self-governing island democracy to be part of its territory.

Only 17 mainly small, developing countries now recognize Taiwan as a sovereign nation. Taiwan split from mainland China amid a civil war in 1949, and Beijing has been steadily ratcheting up diplomatic and economic pressure since Taiwanese President Tsai Ing-wen took office in 2016.

Beijing's aggressiveness is largely driven by Tsai's refusal to endorse Beijing's "one-China principle," which maintains that Taiwan is part of China and that the Communist Party-ruled administration in Beijing is China's sole legitimate government.

Taiwan has long been a wedge between China and the United States, which has formal relations with Beijing but maintains robust unofficial military and diplomatic links with the island.

Washington's de facto ambassador to Taiwan, Brent Christensen, said Wednesday that the U.S. would be opposed to "unilateral attempts to change the status quo" in Taiwan — a nod to increasing Chinese military intimidation.

China's wooing of Taiwan's allies in what U.S. considers its backyard has rung alarm bells in Washington.

The U.S. pulled its diplomatic envoys last month from El Salvador, Panama and the Dominican Republic after those countries cut ties with Taiwan.

At a conference in Washington attended by Salvadoran Vice President Oscar Ortiz last month, Vice President Mike Pence said El Salvador and other Central American countries should strengthen bonds with the U.S. "even as countries like China tries to expand their influence in the region."