TEGUCIGALPA, March 14 (Reuters) - Honduras President Xiomara Castro said on Tuesday she had instructed the country's foreign minister to bring about the opening of official relations with China, a move that threatens to further diminish Taiwan's dwindling pool of allies.

Castro made the statement on Twitter.

The leader of the Central American country had floated the idea of cutting ties with Taiwan and starting relations with China during her electoral campaign, but said in January 2022 she hoped to maintain ties with Taiwan.

China has intensified pressure to reduce Taiwan's international footprint, saying the democratically governed island is Chinese territory with no right to state-to-state ties.

Castro said in the tweet the decision is "a sign of my determination to fulfill the government plan and expand borders."

Honduras' foreign ministry did not immediately reply to a request for comment on the announcement.

Opposition lawmaker Tomas Zambrano told local TV the decision would likely affect the country's relationship with the United States, its top trade partner, noting that many families depend on remittances sent from the north.

China does not allow countries with which it has diplomatic relations to maintain official ties with Taiwan.

If Honduras breaks off its relations with Taiwan, it would leave Taiwan with formal diplomatic ties with only 13 countries.

Taiwan's foreign ministry said it was "in the process of understanding" the situation, without giving further details.

A source familiar with the situation in Taiwan said the island needed to exhaust "every possible means" to maintain diplomatic ties with Honduras.

In December 2021, Nicaragua broke its longstanding ties with Taiwan, switching allegiance to China and declaring that "Taiwan is an inalienable part of the Chinese territory."

The U.S. State Department had at the time encouraged countries to maintain their ties with Taiwan and said Nicaragua's decision did not reflect the will of the people as its government was not freely elected.

The U.S. State Department did not immediately respond to a request for comment regarding Honduras.

Within Latin America, Guatemala, Belize and Paraguay are among the few countries that are still among Taipei's allies.