MYANMAR'S powerful military has triggered worry about a coup after threatening to "take action" over alleged fraud in a November election won by the party of Aung San Suu Kyi, just days before a new parliament convenes.

The military's allegations of voter list irregularities have been accompanied by cryptic comments about abolishing the constitution that have captured public attention and raised the spectre of a coup in a country ruled by the military for half a century after a 1962 military takeover.

The National League for Democracy (NLD) led by Suu Kyi, a former political prisoner and figurehead of Myanmar's long struggle against dictatorship, won 83% of available seats in the Nov. 8 election seen as a referendum on her fledgling democratic government.

WHY IS THE MILITARY CHALLENGING THE VOTE

The military alleges discrepancies such as duplicated names on voting lists in scores of districts and is unhappy with the election commission's response to its complaints.

The military has been guarded about its motives and has not said if irregularities were substantial enough to have changed the election outcome.

Its grievance is similar to that of the Union Solidarity and Development Party (USDP), the former ruling party created by the military before it officially ceded power in 2011.

The USDP, widely seen as a military proxy, was humiliated in the election, winning only 33 of 476 available seats.

WHY IS THE MILITARY GETTING INVOLVED?

As the architect of Myanmar's 2008 constitution and fledgling democracy, the military, known as the Tatmadaw, sees itself as the guardian of national unity and the constitution, and it has enshrined a permanent role for itself in the political system.

It gets an unelected quota of 25% of parliamentary seats and it controls the defence, interior and borders ministries, ensuring an important stake in politics, which has made for an awkward power-sharing arrangement with the NLD, many members of which suffered imprisonment and persecution by the former junta.

Columnist San Yu Kyaw said the political positioning was a last-ditch show of power by the military top brass before their mandatory retirement.

"The political ambitions of Tatmadaw leaders have not been reached so they are acting this way," he said.

WHAT HAS THE NLD, OTHER PARTIES SAID?

Suu Kyi has not commented on her party's election victory, nor on the military's complaints, but the NLD said the military's allegations were groundless and any election flaws would not have changed the outcome.

Of the more than 90 parties that contested the vote, at least 17 have complained of mostly minor irregularities and all except the USDP are smaller parties. Election observers have said the voting was without major irregularities.

The election commission on Thursday said there were no errors on a scale that could mean fraud or the election being discredited.

WHAT IS THE MILITARY PLANNING TO DO?

The spokesman for the armed forces, Brigadier General Zaw Min Tun, held a news conference on Tuesday to renew the allegations but gave a succession of non-committal answers to questions about the military's intentions.

He said the military would "take action", and use all available options including the Supreme Court. Asked if the military would cooperate with the new government and legislature, he told reporters "wait and watch".

Asked if he would rule out a coup, Zaw Min Tun said "cannot say so".

The military spokesman did not answer phone calls seeking comment on Friday.

IS A COUP LIKELY?

The constitution makes it difficult for the military to legally intervene against an elected government.

The commander-in-chief can take power only in extreme circumstances that could cause "disintegration of the union, disintegration of national solidarity and loss of sovereign power", but only during a state of emergency, which can only be declared by the civilian president.

To take power by force, it might have to breach its own constitution.

The commander-in-chief, Senior General Min Aung Hlaing, caused intrigue on Wednesday when he told military personnel a constitution was a "mother law for all laws" and if not abided by, it should be revoked. He cited previous instances when that had happened in Myanmar.

Legal expert Khin Maung Zaw said talk of scrapping the constitution was unreasonable.

"I wonder if they want to abolish it because they cannot protect their own interests," said Khin Maung Zaw.