Taiwan expressed surprise on Thursday when Paraguay’s top opposition presidential candidate questioned the merits of maintaining relations with Taipei, only a month after Beijing severed ties with another Latin American country.

In the election at the end of the month, Efrain Alegre, the leader of the center left Concertacion Nacional alliance, is viewed neck and neck in opinion polls with governing party candidate Santiago Pena.

Alegre has criticized Paraguay’s current diplomatic relations with Taiwan going back over 60 years, which have made it hard to sell soy and beef to China, a major global buyer, and has said Paraguay does not benefit enough from its Taiwan ties.

Speaking to reporters in Taipei, Taiwan Foreign Minister Joseph Wu said Alegre’s public comments “certainly have caused some perplexity”.

“But our colleagues in Paraguay have very close ties with the political parties, the camps and the candidates,” he added.

“Paraguay has had a long-standing relationship with us, and this relationship is also very stable. We will do our best to maintain diplomatic relations with Paraguay.”

Paraguay is one of only 13 countries to maintain formal diplomatic ties with Chinese-claimed Taiwan, and China has been stepping up efforts to win over the island’s remaining allies.

Honduras severed ties with Taipei in favor of Beijing last month.

China has long argued that democratically ruled Taiwan is part of its own territory with no right to state-to-state ties, a position Taipei strongly rejects.

China demands that countries it has ties with must adopt its position that Taiwan is Chinese territory.