Taiwan President Tsai Ing-wen casts her vote for the local elections in New Taipei City, Taiwan, November 24, 2018. Chang Haoan/Pool/via REUTERS

TAIPEI (Reuters) - Taiwan President Tsai Ing-wen said on Saturday she was resigning as chairwoman of the ruling Democratic Progressive Party after mayoral election defeats.

Tsai also told a news conference that she had not accepted the resignation of her premier, William Lai, who had offered to quit earlier in the evening.