BEIJING - China and El Salvador established diplomatic relations Tuesday as the Central American nation ditched Taiwan in yet another victory for Beijing in its campaign to isolate the island.

Beijing has been using its economic clout to peel away international support for the democratically-ruled island, leaving it with only 17 diplomatic allies around the world.

Speaking in Beijing at the Diaoyutai Guest House, Chinese Foreign Minister Wang Yi praised El Salvador's decision to "recognise there is one China in the world".

"This further goes to show the One China policy is in line with international norms, is the correct choice... and is the basis of China's relation with any country," he said.

Salvadoran Foreign Minister Carlos Castaneda, after signing a document with Wang establishing relations, said his country had made a "strategic decision" and taken the "correct and beneficial path for the people of both nations".

The president of El Salvador, Salvador Sanchez Ceren, said in an address on national television Monday night: "We are convinced that this is a step in the right direction, which corresponds to the principles of international law, international relations and the inevitable trends of our day."

The announcement in Beijing followed a decision by Taiwan to sever its ties with El Salvador after it learnt the country was planning on recognising Beijing.

"Losing (a) diplomatic ally is not an isolated incident. It is part of China's string of sabre rattling and intimidation," Taiwan President Tsai Ing-wen said at a press conference in Taipei.

The news came just after Tsai, who is trying to raise Taiwan's international profile, wrapped up a Latin American tour which included stops in the United States, which drew criticism from China. She visited allies Belize and Paraguay during the trip.

Taiwan's foreign minister Joseph Wu said Taipei "will not engage in dollar diplomacy with China", adding that El Salvador had been asking for "huge funding" for a port development project, which Taiwan was unwilling to give because it would leave both countries in debt.

- 'No pre-conditions' -

El Salvador's move leaves Taiwan with a dwindling number of allies around the world as more countries switch recognition to China, which sees the self-ruling democratic island as a renegade part of its territory.

"El Salvador has made the choice to commit itself to one China with no pre-conditions, thus standing with most countries in the world," Wang said in comments that seemed intended to pre-empt Taiwanese accusations that China had bought the small Latin American nation's loyalty.

But, he added, the country "will get tangible gains from its partnership with China".

Tsai said this was a clear sign of China's continuing pressure, and had moved beyond being just a cross-strait issue.

"China's intention in the Asian region (is evident), especially to challenge or even replace (the) international order led by traditional powers," Tsai said.

"China intends to highlight its influence and power in the region through intensifying pressure on Taiwan."

Relations between Taipei and Beijing have worsened since Tsai came to power as her government refuses to acknowledge that Taiwan is part of "one China".

China has stepped up its poaching of Taiwan's allies since Tsai became leader in 2016.

El Salvador is the fifth diplomatic loss under her presidency and the third this year, following Burkina Faso and the Dominican Republic.

The small African nation of Sao Tome switched recognition to Beijing in late 2016, followed by Panama in June last year.

Taiwan and China have been engaged for years in a diplomatic tug-of-war in developing countries. Economic support and other aid are often used as bargaining chips for diplomatic recognition.

Tsai's government is trying to enhance Taiwan's international profile but faces a concerted attempt by Beijing to shrink its space on global platforms.

Beijing has stepped up pressure on her government by blocking Taiwan from attending a growing list of international events and staging a string of military drills around the island.