Myanmar's election commission on Sunday scrapped November by-elections in 35 parliamentary seats, citing the pressure of hosting an upcoming regional summit and extra costs ahead of a nationwide poll in 2015.
The Union election commission made the surprise announcement after a meeting with more than 30 political parties in Yangon.
Explaining the decision, deputy director of the commission Hla Maung Cho said the number of lawmakers who would have been returned to parliament in the by-elections "will not make a big difference" to voting.
He cited Myanmar's chairing of the Association of Southeast Asian Nations (ASEAN) summit in November and high cost of contesting polls for smaller political parties who are also planning their campaigns for the nationwide vote slated for November next year.
The opposition National League for Democracy (NLD) secured a landslide victory in by-elections in April 2012, sending party leader Aung San Suu Kyi to parliament as the nation pressed forward with democratic reforms after decades of military rule.
Suu Kyi's party is widely tipped to sweep full polls in 2015, if they are free and fair.
An NLD spokesman welcomed the cancellation of the by-elections.
"They were pretty rushed," Nyan Win of Suu Kyi's party told AFP.
"Now, we can prepare better for general election."
Suu Kyi is trying to change key sections of Myanmar's constitution that could open the way for further tweaks to the charter, including the ring-fenced proportion of soldiers in parliament and the effective bar on Suu Kyi leading the country.
As it stands, she is ineligible because of a clause in the 2008 charter blocking anyone whose spouse or children are overseas citizens from leading the country. Suu Kyi's two sons are British.
To alter the constitution a majority of more than 75% of parliament is required.
Unelected soldiers make up a quarter of the legislature and therefore have the last say on any changes.
Parliament is due to resume after a break on Thursday, with a controversial debate on adopting a proportional representation voting system likely to be on the agenda during the new session.
Backers of a proportional system say it will give minority parties in the ethnically diverse country a greater stake in decision making.
But critics say it is an attempt to prevent an NLD landslide in 2015.