Thailand's embattled premier announced Wednesday he might lift an emergency decree that has failed to stifle a growing protest movement demanding his resignation and reforms to the monarchy.

After a day of anti-government and rival royalist protests across the country, thousands of angry democracy activists marched on Government House, defying an emergency decree imposed last week banning gatherings of more than four people.

Protesters marched from Victory Monument during an anti-government rally in Bangkok
Protesters marched from Victory Monument during an anti-government rally in Bangkok AFP / Mladen ANTONOV

As they chanted for him to resign, Prime Minister Prayut Chan-O-Cha addressed the nation, saying he would make "the first move to de-escalate" the situation.

"I am currently preparing to lift the state of severe emergency in Bangkok and will do so promptly if there are no violent incidents," he said, without specifying any timeframe.

"We must now step back from the edge of the slippery slope that can easily slide to chaos," he added, calling on protesters to resolve their differences through parliament.

Royalist supporters took part in a rally to show support for the Thai establishment in the southern province of Narathiwat
Royalist supporters took part in a rally to show support for the Thai establishment in the southern province of Narathiwat AFP / Madaree TOHLALA

Democracy activists had massed at Bangkok's Victory Monument, while counter-rallies attracted thousands of royalists in the southern province of Narathiwat and scores more in the capital.

AFP journalists in Bangkok said some minor scuffles broke out between rival factions before around 7,000 pro-democracy activists set off towards the seat of the executive.

Protesters marched from Victory Monument during an anti-government rally in Bangkok
Protesters marched from Victory Monument during an anti-government rally in Bangkok AFP / Mladen ANTONOV

A line of around 150 riot police and barbed wire stopped the crowd about two kilometres (1.2 miles) from their target, although protesters soon managed to push their way through.

As they kept up their chants, one group even waved a giant "resignation letter" for the premier from the top of buses parked just a couple of hundred metres away from the building's gates.

"Prayut said we should take one step back together. We will step back when Prayut resigns and stops taking legal action against our friends," one protester shouted to the crowds, reading out a statement.

Protesters are demanding the powerful and ultra-wealthy monarchy stay out of politics
Protesters are demanding the powerful and ultra-wealthy monarchy stay out of politics AFP / Lillian SUWANRUMPHA

"If Prayut's government does not resign within three days, they will see us again," warned another activist to chants of, "Prayut, get out!" and "Monarchy reform!", before they all dispersed.

Democracy protesters have assembled daily in the capital since last week, flouting the emergency edict as their calls for Prayut to go intensified.

Some minor scuffles broke out between rival factions
Some minor scuffles broke out between rival factions AFP / Jack TAYLOR

The former army chief masterminded the 2014 coup and demonstrators say the military-drafted constitution rigged last year's vote in his favour.

Activists are also demanding the powerful and ultra-wealthy monarchy stay out of politics -- a previously taboo subject.

The emergency decree was issued after a group of protesters surrounded the queen's royal motorcade, raising their arms in a three-fingered salute of defiance, inspired by the "Hunger Games" movies.

Pro-democracy protesters pushed barricades past barbed wire as riot police stood guard
Pro-democracy protesters pushed barricades past barbed wire as riot police stood guard AFP / Mladen ANTONOV

On Friday the use of force escalated as riot police deployed water cannon against the unarmed activists and scores of demonstrators have been arrested.

Earlier on Wednesday, Bangkok's criminal court backtracked on a ruling that ordered Voice TV -- partly owned by exiled former premier Thaksin Shinawatra -- to close over its coverage of pro-democracy rallies.

The website was one of four media outlets under investigation for violating computer crimes laws and an emergency decree aimed at curbing the civil unrest.

But the court revoked the ruling, allowing all four to continue reporting freely.

The court said there "must be specific content that is illegal and authorities cannot shut down a whole page or URL," Voice TV's lawyer Winyat Chartmontri told reporters.

"The court said people's freedom (of) communication must be protected and media outlets can not be shut down. Press freedom is very crucial," he said, adding that today's decision cannot be appealed.

Voice TV staff would continue their reporting duties "fully, professionally and factually", said a statement on the outlet's website.

Sunai Phasuk from Human Rights Watch hailed the court decision but warned journalists were still at risk as their presence at protests is considered a violation of the emergency decree.

"They are not out of the woods yet."

Activist Nat, 26, told AFP she was happy the court ruling had been overturned.

"We will still have a TV channel that reports the truth," she said, urging for the freedom to protest to be returned too.

But since senators are appointed by the government and many come from military ranks, they are unlikely to willingly give up their power, said political analyst Thitinan Pongsudhirak.

"It's almost a moot point. It's buying time," he told AFP.