Myanmar President U Thein Sein, who will pay a landmark visit to Washington this month, has resigned as chairman of the ruling Union Solidarity and Development Party (USDP) and his party post was replaced by its vice chairman U Shwe Mann, according to the party's Union Daily Thursday.

In accordance with the 2008 constitution, "if the president and the vice presidents are members of a political party, they shall not take part in its party activities during their term of office from the day of their election."

Because party chairman U Thein Sein was also fulfilling the role of president, U Shwe Mann, who is first vice chairman, helped him by taking on some of the party chairman responsibilities.

U Thein Sein's dual posts of government and party have received criticism, so the handover of the party chairman's post was formerly announced at a three-day party youth function Wednesday.

Chairman U Shwe Mann, who also holds the post of Speaker of the House of Representatives (Lower House), stressed the safeguarding of the multi-party democratic system as well as market-oriented economic system.

After relinquishing his military title of general, U Thein Sein formed the USDP in April 2010 to run the November 2010 general election, in which the USDP won the majority of the parliamentary seats, becoming the ruling party, and U Thein Sein was elected to the House of Representatives.

In 2011, U Thein Sein won the presidential election, and was then sworn in to office. On October 17, 2012, the USDP held its first party conference in Nay Pyi Taw but made no major change in terms of the structure of the top leadership.

There are 58 legal political parties in Myanmar. The USDP and the National League for Democracy are the most powerful.

Xinhua - AFP