The commander of Burma's armed forces has defended the army's role in national politics and says he will protect the Southeast Asian nation's pro-military constitution.

General Min Aung Hlaing spoke Tuesday to more than 10,000 troops at an annual parade marking Armed Forces Day.

He said unelected members of the military, who fill 25 percent of seats in the 440-member lower house of parliament, are acting in the national interest and performing a national duty.

“Article 20 of the national constitution clearly states that the army has a fundamental duty to protect the constitution. So I would like to say that protecting the constitution is one of the main responsibilities of the army as we build our country into becoming a modern, prosperous and developed democracy.''

The parade, which commemorates the army's 1945 uprising against Japanese military rule in World War Two. was the first since a nominally civilian government took power one year ago, ending more than four decades of direct military rule.

The general's comments come ahead of Sunday's parliamentary by-elections, as pro-democracy leader Aung San Suu Kyi and her National League for Democracy party campaign for legislative seats.

The NLD is seeking to fill 45 vacancies in the legislature, including a post sought by the Aung San Suu Kyi near Rangoon.

The Nobel laureate spent much of the past two decades under house arrest. She was released in late 2010 as the ruling military regime prepared to cede power.