National League for Democracy (NLD) party Information Department In-charge Monywa Aung Shin confirmed to Mizzima that one of the party’s top leaders, Win Htein, has sent a resignation letter to Aung San Suu Kyi through party.
The NLD party confirmed the tendering of a resignation letter on 16 March by CEC member Win Htein, asking to relieve him from party duty.  
Currently Win Htein is in Australia and he tendered his resignation letter one month after his departure from Myanmar.
It is learned that this matter will not be discussed at the moment but is likely to be discussed at the upcoming CEC meeting.
Win Htein left for Australia on January 14 for a medical visit after the marriage reception of his son and he met with NLD Party leader Aung San Suu Kyi before his departure.
Former army captain Win Htein, aged 77, joined the NLD party at its inception in 1988 and he was imprisoned for his political activities for the first time from 1989 to 1995 and then the second time in 1996. He was released in 2008 but rearrested within 24 hours and finally released in 2010. He was elected MP in House of Representatives in 2012 by-elections and he did not contest in the 2015 general elections.
When party chairperson Aung San Suu Kyi took charge of the government, the central secretariat of party central executive committee was formed and he was in this committee along with Nyan Win, Win Myint, Dr. Zaw Myint Maung, and Han Thar Myint.