Former Taiwan President Tsai Ing-wen will visit the Czech Republic this month, three sources briefed on the matter said, a sensitive visit for a senior politician who Beijing has repeatedly denounced as a "separatist."

The Czech Republic, like most countries, has no official diplomatic ties with Chinese-claimed Taiwan, but the two sides have moved closer as Beijing ratchets up military threats against the island and Taipei seeks new friends in Eastern and Central Europe.

Tsai, who stepped down in May, will visit Prague and deliver a speech at Forum 2000, which begins on Oct. 13, said the three sources, speaking on condition of anonymity given the sensitivity of the matter.