The new regulation comes amid heated internal debate over how the pro-independence Democratic Progressive Party should deal with the mainland while overall China-Taiwan ties are improving.

Party spokesman Cheng Wen-tsang said the regulation requires party lawmakers, magistrates, mayors and senior members to report any plan to visit China.

"This is to help the party monitor exchanges between our senior members and China," Cheng told The Associated Press. "The DPP will approve of the visits or not depending on whether Chinese authorities are trying to use the trips to promote Taiwan's unification with China."

Cheng did not say what would happen if a member defies the party's disapproval.

Taiwan and China split amid civil war in 1949, but Beijing continues to claim the island as part of its territory -- a stance the DPP rejects.

The new regulation follows a high-profile visit to China earlier this year by Chen Chu, mayor of Taiwan's second-largest city, Kaohsiung.

Chen is the highest-ranking DPP official to visit the mainland. Some party members objected to the visit, saying it could undermine the party's pro-independence stance. But Chen pledged to uphold Taiwanese sovereignty, and most party members were satisfied she had fulfilled her promise.

The DPP lost last year's presidential election to the Nationalist Party's Ma Ying-jeou, who promotes closer ties with Beijing. Relations between Taiwan and the mainland have warmed since Ma's election.

Members of the Nationalist Party have visited China with few restrictions for years, in keeping with the party's agenda of promoting closer relations. High-ranking government officials and personnel with access to highly classified information need special permission.