Myanmar President Htin Kyaw resigned on Wednesday, according to a statement posted on the official Facebook page of the President's Office, in a move believed prompted by ill health.

The official statement in the Myanmar language said "the President of the Union of Myanmar, U Htin Kyaw, has resigned from his post effective today March 21, as he would like to retire from his current duties."

No further reason has been given for the resignation of Htin Kyaw, a civilian, from the largely ceremonial post.

Htin Kyaw, close friend of Myanmar's de facto leader and State Counselor Aung San Suu Kyi, became president in March 2016 following the National League for Democracy's landslide election victory in November 2015.

Htin Kyaw's health has been deteriorating since he underwent, according to a Predident's Office statement at the time, surgery last September in Bangkok following discovery of a polyp in his colon.

He also reportedly received brief medical treatment during an official visit to Japan last December.

Suu Kyi chose Htin Kyaw as a presidential candidate because Myanmar's Constitution -- drafted and approved in 2008 during military rule -- barred her from becoming president because she was married to a foreigner and has two sons with British citizenship.

Htin Kyaw, a former civil servant with a humble low-profile character, later created the special position of State Counselor for Suu Kyi and transferred virtually all his authority to her so she could run the country as leader.

The procedure to fill the vacant post of president within seven working days will be implemented in accordance with the Constitution of Myanmar, the presidential office statement said.

Myint Swe, a former army general, has become the acting president as he received the second most votes in the 2016 presidential election.

Myanmar has two vice presidents, and Myint Swe was the senior of the two by virtue of finishing second in the 2016 presidential election.

Myint Swe was put forth as a candidate in the 2016 election by the military members of parliament. All members of parliament then voted to choose the president from the three candidates nominated to run.

Wednesday afternoon the parliament also announced that Win Myint had resigned as Speaker of the Lower House, prompting domestic media speculation that he would become the next president.

Win Myint, 66, is also a close aid of Suu Kyi and belongs to her ruling party. He became the speaker in 2016 after winning a lower house seat for a second term in the November 2015 elections.

Formerly a lawyer, Win Myint became a political prisoner for his role in the 1988 popular uprising against military rule. He later joined Suu Kyi's party and won a seat in the 1990 general elections, whose results the military later nullified.

Under Myanmar law, the lower house shall elect a new speaker as soon as possible, and nominate someone to run against the existing two vice presidents to fill the vacant post of president.