Myanmar election: President congratulates Suu Kyi
Myanmar President Thein Sein has congratulated Aung San Suu Kyi's opposition party on its success in polls, his spokesman told the BBC.
With about 47% of seats declared, the National League for Democracy (NLD) has taken over 90% of the vote.
Ms Suu Kyi has written to the leadership requesting talks on national reconciliation.
But spokesman U Ye Htut said such a meeting could only take place after the final results were announced.
He insisted there was no attempt to delay the declaration of results from Sunday's election.
Correspondents say Ms Suu Kyi is treading carefully despite her apparent landslide victory. The NLD won elections decisively in 1990 - only for the result to be nullified and Ms Suu Kyi placed under long-term house arrest.
The ruling military-backed Union Solidarity Development Party (USDP) - which won the last, widely criticised election five years ago - has so far gained only 5% of the seats being contested in Myanmar, known as Burma.
A quarter of seats are reserved for the military.
Ye Htut said US President Barack Obama had called Myanmar President Thein Sein to "congratulate him and the government for successfully holding a historic free and fair general election" and posted online pictures showing Thein Sein on the phone.
The US State Department has yet to confirm the phone call.
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"Our message to the people of the country on behalf of U Thein Sein is that President U Thein Sein wants to congratulate the Myanmar people for the free and fair and very peaceful election day," U Ye Htut told the BBC.
"And second he also wants to congratulate the NLD for their success in the election."
"Our government will respect the people's decision and choice and will hand over power as scheduled," President Thein Sein also pledged in a post on his Facebook page.
The result so far is a humiliation for the governing party, says the BBC's Jonathan Head in Yangon, also known as Rangoon.
It is likely to leave the NLD in a commanding position in the next parliament, opposed only by the military faction, he says.
Ms Suu Kyi earlier retained her own seat and will return as MP for her Kawhmu constituency in Rangoon. Although she leads the NLD she is barred by the constitution from being president.
But she has said that will not stop her "from making all the decisions".
In her letters sent Tuesday to the president, the commander of the armed forces and the parliamentary speaker she requested a meeting next week to discuss "a peaceful implementation of the people's desire, which they expressed via the 8 November election".
Aung San Suu Kyi - 'The Lady'
- 70-year-old daughter of Myanmar's independence hero, Gen Aung San
- Spent 15 years under house arrest between 1989 and 2010, despite the NLD winning a landslide in elections in 1990 which were later nullified
- Awarded the Nobel Peace Prize in 1991 for "her non-violent struggle for democracy and human rights"
- Sidelined in 2010 elections but released from house arrest six days later
- Won a parliamentary seat in 2012 by-election, as country adopted liberalising reforms
The ruling party has now indicated that it will not attend any meeting until after the final tally of election results is announced. There is no official prediction of when that might be.
A quarter of the 664 parliamentary seats are set aside for the army. A handful are not being contested, leaving 491 seats.
For the NLD to have the winning majority and be able to select the president, it will need at least two-thirds of the remaining seats - 329.
By Wednesday evening, the NLD had taken 256 seats across both houses of parliament, while the USDP, which has been in power in Myanmar since 2011, had 21.
About 30 million people were eligible to vote in Sunday's election in Myanmar. Turnout was estimated at about 80%.
Hundreds of thousands of people - including the Muslim Rohingya minority, who are not recognised as citizens - were denied voting rights.
Nonetheless, Sunday's election was seen as the most democratic in Myanmar for 25 years.
In an interview with the BBC on Tuesday, her first since the vote, Ms Suu Kyi said the polls were "largely free" though not entirely fair, and that there had been some irregularities.