The party of opposition leader Aung San Suu Kyi claimed victory Monday in virtually every seat in the four states where results of Burma's historic parliamentary election were known.

Those early results signal a sweep that could give it the presidency and further loosen the military's stranglehold on the Southeast Asian country also known as Myanmar.

The announcement at the headquarters of the National League for Democracy set off a new round of jubilation among the party's red-shirted supporters, who already had been celebrating the result of Sunday's vote.

The National League for Democracy announced that it had won 44 of the 45 lower house seats and all 12 of the upper house seats from the party's stronghold of Rangoon, in Sunday's general election.

It also won all 38 seats in Ayeyarwaddy state, all but one of the 40 in Bago, and 11 out of 19 lower house seats and all 10 upper house seats in Mon state.

That trend was expected to continue in Myanmar's remaining 10 states.

Even without official results, it was clear that the Union Solidarity Development Party was facing a rout. The party is made up former junta members who ruled the Southeast Asian country for a half-century and continued to wield influence as a quasi-civilian government after 2011.

Many of the party's leaders conceded personal defeats in their races Monday.

The United States congratulated Burma on the election but noted that more work remains ahead on the country's road to democracy.

The Rangoon result was not announced by the government's Union Election Commission, but the NLD has stationed representatives at counting centers and is keeping tallies that are being relayed to its headquarters. The election commission has been slow in releasing the numbers.

Earlier, Suu Kyi, the Nobel Peace Prize laureate and pro-democracy icon, urged supporters not to provoke losing rivals who mostly represent the former junta that ruled this Southeast Asian nation, also known as Myanmar, for a half-century.

Supporters sing a song for Burmese pro-democracy leader Aung San Suu Kyi as they wait for official election results in front of National League for Democracy Party (NLD) head office in Rangoon Monday. (Soe Zeya Tun/Reuters)

Hours before the Rangoon announcement, party spokesman Win Htein said the NLD had won about 70 percent of the votes counted by midday. Another spokesman, Nyan Win, put the number at 90 percent.

"We will win a landslide," Nyan Win told The Associated Press.

The comments, if confirmed by official results from Sunday's general election, indicate that Suu Kyi's party would not only dominate parliament, but could also secure the presidency despite handicaps built into the constitution.

"I want Mother Suu to win in this election," said Ma Khine, a street vendor, referring to the 70-year-old Suu Kyi with an affectionate term many here use. "She has the skill to lead the country. I respect her so much. I love her. She will change our country in a very good way."

Seats reserved for military

The NLD has been widely expected to finish with the largest number of seats in parliament. A two-thirds majority would give it control over the executive posts under Myanmar's complicated parliamentary-presidency system, which also reserves 25 percent of parliament's 664 seats for the military.

The military and the largest parties in the upper house and the lower house will each nominate one candidate for the presidential election, which will be held after Jan. 31. Then all 664 legislators will take a vote and the person with the highest number of ballots will become president, while the other two will become vice presidents. A massive majority in Parliament would allow the NLD to take the presidency and one vice presidency.

Capturing the presidency and parliament would give the NLD power over legislation, economic policy and foreign relations, but the constitution guarantees that the military would retain control over the ministries of defence, interior and border security. Also, the military will have the power to legally block constitutional amendments.

Suu Kyi cannot be president

Also, Suu Kyi cannot become the president. A constitutional amendment bars anyone with a foreign spouse or child from being president or vice president. Suu Kyi's two sons are British, as was her late husband. Suu Kyi, however, has said she will act as the country's leader if the NLD wins the presidency, saying she will be "above the president."

In any case, it was clear that the ruling Union Solidarity Development Party, made up former junta members and which has ruled as a quasi-civilian government since 2011, was facing a rout. Many of its leaders conceded personal defeats in their election bids.

In her first comments after the elections, Suu Kyi told a crowd gathered at the NLD's headquarters: "I want to remind you all that even candidates who didn't win have to accept the winners, but it is important not to provoke the candidates who didn't win to make them feel bad."

"I am so happy, and I am not the only person — the whole country is happy," said 71-year-old Khin Maung Htay, who was listening to Suu Kyi's speech. "I think she is a perfect leader for our country and a woman of perfection."