The vote to appoint a new president in Myanmar has been brought forward by a week, to 10 March.
The move likely means an end to negotiations on whether the constitution could be amended so Aung San Suu Kyi could take the top job.
Suu Kyi's National League for Democracy (NLD) won a general election landslide victory in November and will take office at the end of the month.
But she is barred by the constitution from being the president.
A clause, widely seen as having been included to target her, means anyone who has foreign children cannot take the post.
She has consistently said she will effectively lead the country anyway.
The new president will be elected by the upper and lower house from a list of three candidates put forward by MPs.
The original date for the vote had been 17 March, which was seen as giving time for the NLD to negotiate with the military about a possible change to, or suspension of, the constitution.
But the BBC's Jonah Fisher in Yangon says several meetings between Suu Kyi and the army commander-in-chief appear to have yielded little result. Bringing the date forward by a week effectively closes the window for further talks, he adds.
The NLD dominates both houses after taking 80% of contested seats in the election. But the military, which ran Myanmar for decades, still has an automatic 25% of all seats.
The new president, says our correspondent, is still certain to be Suu Kyi's preferred candidate, likely to be one of her trusted aides.
NLD official Win Htein told the BBC the party would now focus on trying to change the constitution from within.
"Aung San Suu Kyi will still become president anyhow. It's only the matter of sooner or later," he said.