TAIPEI (REUTERS) - Taiwan will host a group of Lithuanian lawmakers next week amid a deepening spat between Beijing and Vilnius about the Baltic state's decision to allow the island to open a de facto embassy.

Beijing on Sunday (Nov 21) downgraded diplomatic ties with Lithuania in a further show of anger over the issue.

China regards Taiwan as a renegade province to be reunified, by force, if necessary.

Taiwan's Foreign Ministry said on Wednesday (Nov 24) that Mr Matas Maldeikis, leader of the Lithuanian Parliament's Taiwan friendship group, would visit Taipei to attend a legislative forum from Dec 2 - 3, along with other colleagues and lawmakers from Latvia and Estonia.

Ten representatives from the three Baltic states will be participating.

The group will also meet Taiwan President Tsai Ing-wen along with other senior officials, the ministry added.

Beijing had already expressed its anger this summer with Lithuania - which has formal relations with China and not Taiwan - after it allowed the island to open an office in the country using the name Taiwan. China recalled its ambassador in August.

Other Taiwan offices in Europe and the United States use the name of the city Taipei, avoiding reference to the island itself. However, the Taiwanese Representative Office in Lithuania finally opened last week.

Washington has expressed its concern at China's reaction and offered Vilnius support to withstand Chinese pressure.

Only 15 countries have formal diplomatic ties with Taiwan.