Anti-coup protesters across Myanmar defied a new military ban on rallies and took to the streets Tuesday for a fourth straight day, as international condemnation swelled against the putsch.

After watching hundreds of thousands of people rally in opposition to last week's coup, junta chief General Min Aung Hlaing made a televised speech on Monday evening to justify seizing power.

His statement came as the military banned gatherings of more than five people in parts of Yangon, the nation's commercial capital, and other areas across the country where major rallies had erupted over the weekend and on Monday.

A nighttime curfew was also imposed at the protest hotspot sites.

But on Tuesday morning, fresh protests emerged in various parts of Yangon, including near the headquarters of the National League for Democracy (NLD), the party of deposed leader Aung San Suu Kyi, who the military detained on day one of the coup.

The protesters carried anti-coup placards including "We want our leader", in reference to Suu Kyi, and "No dictatorship".

In San Chaung township -- where large gatherings were specifically banned -- scores of teachers marched on the main road, waving a defiant three-finger salute that has become the trademark sign of the protesters.

"We are not worried about their warning. That's why we came out today. We cannot accept their excuse of vote fraud. We do not want any military dictatorship," teacher Thein Win Soe told AFP.

Neighbouring Kamayut township -- another area where gatherings are banned -- had hundreds of protesters amass in defiance, singing songs and waving posters.

In the capital Naypyidaw, police repeatedly fired water cannon against a small crowd of protesters, who withstood the barrage and refused to retreat.

"End the military dictatorship," people in the crowd yelled as the water cannon was fired.

- Military promises -
In his televised address, his first since the coup, Min Aung Hlaing insisted the seizure of power was justified because of "voter fraud".

The NLD won last November's national elections by a landslide but the military never accepted the legitimacy of the vote.

Shortly after the coup, the military announced a one-year state of emergency and promised to then hold fresh elections.

Min Aung Hlaing on Monday insisted the military would abide by its promises. He also declared that things would be "different" from the army's previous 49-year reign, which ended in 2011.

"After the tasks of the emergency period are completed, free and fair multi-party general elections will be held according to the constitution," he said.

"The winning party will be transferred state duty according to democratic standards."

But those pledges were accompanied by threats.

In the face of the increasingly bold wave of defiance, the military released a statement on state TV on Monday warning that opposition to the junta was unlawful.

"Action must be taken according to the law with effective steps against offences which disturb, prevent and destroy the state's stability, public safety and the rule of law," said the statement read by an announcer on MRTV.

- Global outrage -
The United States has led global calls for the generals to relinquish power, and issued a fresh statement on Monday following the junta's warnings against the protesters.

"We stand with the people of Burma and support their right to assemble peacefully, including to protest peacefully in support of the democratically elected government," US State Department spokesman Ned Price said Monday, using Myanmar's former name.

Price also said US requests to speak to Suu Kyi were denied.

New Zealand on Tuesday became the first foreign government to take concrete public action, announcing the suspension of high-level military and political contacts with Myanmar.

Pope Francis on Monday also called for the prompt release of imprisoned political leaders.

"The path to democracy undertaken in recent years was brusquely interrupted by last week's coup d'etat," he told a gathering of diplomats.

"This has led to the imprisonment of different political leaders, who I hope will be promptly released as a sign of encouragement for a sincere dialogue."

The UN Human Rights Council said it would hold a relatively rare special session on Friday to discuss the crisis.

New Zealand suspends ties

New Zealand announced the suspension of high-level military and political contacts with Myanmar Tuesday, the first major international move to isolate the country's ruling junta following a coup.

Unveiling the measures, Prime Minister Jacinda Ardern called for the international community to "strongly condemn what we're seeing happen in Myanmar".

"After years of working hard to build a democracy in Myanmar, I think every New Zealander would be devastated to see what we've seen in recent days led by the military," she told reporters.

"Our strong message is we will do what we can from here in New Zealand."

Ardern said the measures would include travel bans on senior military figures.

Myanmar's military last week detained civilian leader Aung San Suu Kyi and dozens of other members of her National League for Democracy (NLD) party, ending a decade of civilian rule.

Ardern said New Zealand wanted the UN Human Rights Council to hold a special session to discuss developments in Myanmar.

She added that New Zealand's aid programmes in Myanmar, worth about NZ$42 million ($30.5 million), would continue with safeguards that they did not benefit, or come under the control of, the military junta.

"We're being very cautious with whatever aid and development work we do there that we are not propping up that regime," she said.

Ardern conceded New Zealand had limited leverage on Myanmar's military but said Suu Kyi had personally thanked her during past meetings for Wellington's help during the country's transition to democracy.

"While it may seem New Zealand's position on this may not seem particularly relevant, one of the last occasions when I had the opportunity to meet and talk with Aung San Suu Kyi, she specifically mentioned some of our representatives from New Zealand in Myanmar," Ardern said.

"They were well regarded and well respected and I think it played a really constructive role in that critical time for Myanmar and their transition."

The junta proclaimed a one-year state of emergency last week, promising to hold fresh elections after that, without offering any precise timeframe.

In doing so they ended Myanmar's 10-year experiment with democracy after close to 50 years of military rule.

The generals justified the coup by claiming fraud in November's elections, which the NLD won by a landslide.

New Zealand Foreign Minister Nanaia Mahuta dismissed the allegations of fraud.

"We do not recognise the legitimacy of the military-led government and we call on the military to immediately release all detained political leaders and restore civilian rule," she said in a statement.