Yang Xiaowei had been in his role for a little over a year.

China Telecom announced on Wednesday the resignation of its chief operating officer, Yang Xiaowei, effective immediately.

Yang had only been in the role for a little over a year.

"Mr. Yang has confirmed that he has no disagreement with the board and did not have any matters in relation to his resignation that should be brought to the attention of shareholders," China Telecom said, in a brief statement. "The board would like to express its sincere gratitude to Mr. Yang for his valuable contribution to the company during his tenure."

China Telecom is the country’s third-largest mobile operator, with 224.05 million connections, which includes 142.58 million 4G connections, at the end of April.

Yang was appointed as COO in April 2016. The change in role was brought about by the sudden departure of CEO Chang Xiaobing in January last year after he became the subject of a corruption investigation.

Chang was replaced by then COO Yang Jie, and Yang Xiaowei became COO.

Meanwhile, at the end of May, Yang Jie, who also once served as chairman and CEO of China Unicom, was sentenced to six years in prison for graft, after he admitted to accepting money and valuables worth 3.76 million yuan (€491,942) between 1998 and 2014.