The red-shirted supporters of Thai Prime Minister Yingluck Shinawatra said on Wednesday they could take to the streets to protect the government from protesters who have forced her to call a snap election, setting the scene for a possible confrontation.
The warning by the "red shirts" highlights the risks ahead as anti-government protesters keep pushing to eradicate the political influence of Yingluck's brother, former premier Thaksin Shinawatra, a hero in the rural north and northeast who was toppled by the military in 2006.
Protest leader Suthep Thaugsuban, a former deputy prime minister in the previous government that Yingluck's ruling party beat by a landslide in 2011, has ignored her call for a snap election to be held on February 2.
He wants Thailand to be governed by an unelected "people's council" made up of appointed "good people". Such an unprecedented move alone would potentially spark conflict with Yingluck's red-shirted supporters in the country of 66 million.
The United Front for Democracy Against Dictatorship (UDD), as the red shirts are known, could rally to protect the government, said Jatuporn Promphan, one of its leaders.
"It is the UDD's job to bring together en masse the red shirts and those who love democracy and don't agree with Suthep's methods. There will be many more people than Suthep managed to gather," he told Reuters in an interview.
Suthep, who a few weeks ago resigned the parliamentary seat he had held for 34 years, derives support from a small but powerful minority: the royalist elite in Bangkok and the opposition Democrats, the country's oldest party, who have failed to win an election since 1992.
In 2010, he authorized a crackdown by security forces that left downtown Bangkok burning and killed scores of red shirts, who say they remain supportive of Yingluck and her billionaire brother Thaksin, who lives in self-exile to avoid jail for abuse of power charges that he says were politically motivated.
Thaksin is widely seen as the power behind Yingluck's government, sometimes holding meetings with the cabinet by webcam. They have huge support in the countryside because of pro-poor policies and any party associated with Thaksin stands a good chance of winning the election.
"When Suthep speaks he should bear in mind that there are millions of Thais who love Thaksin and love the Shinawatra family," Thida Thawornseth, the top UDD leader, told Reuters.
"Where does Suthep come off thinking he can speak on behalf of all Thais?" she added. "Suthep has said Yingluck cannot go anywhere in Thailand without being insulted. What about him? He is the one who should be worried."
The comments from the red shirts suggest the protests could lead to a wider conflict if Yingluck's elected government is forcibly removed.
After courts brought down two Thaksin-allied governments in 2008 and the Democrats came to power through a parliamentary vote believed to be orchestrated by the military, the red shirts built up a street movement that paralyzed Bangkok in April-May 2010 and ended with the bloody military crackdown.
A year later, the Democrats were trounced in an election.
The red shirts cut short a rally on December 1 after fatal clashes around the stadium where it was being held and postponed a mass demonstration that had been planned for Ayutthaya to the north of Bangkok on December 10.
Asked what would bring them out on to the street, Jatuporn said: "When chaos ensues or when Suthep's side uses violent methods to gain power".
He declined to say where the rally could be held but said the aim was not to seek confrontation but to show that the pro-Thaksin forces could bring out more people than Suthep.
After forcing the snap election on Monday, when 160,000 people massed around the prime minister's office, Suthep gave Yingluck 24 hours to step down. She is caretaker prime minister until the election, set for February 2.
After that deadline ran out on Tuesday night, Suthep said police should arrest her.
"I ask police to arrest Yingluck for treason because she did not meet our orders," he told supporters still camping out at Government House.
Before the deadline had elapsed, he said: "If you don't listen, we will escalate our protest until you and the rest of the Shinawatra family are unable to stand it anymore.
"How long will you be able to stand it if people spit on your car every day?" he said. In previous speeches he has said the whole Shinawatra family should leave the country.
Suthep says the government has violated the constitution in several ways. In return, he has been charged with insurrection.
So far no attempt has been made to arrest him.
In his speech, Suthep urged the military, traditionally close to the royalists, to take control of government buildings in place of the police, who are closer to Thaksin, himself a former police officer.
The politically powerful army, which has staged or attempted 18 coups in the past 80 years, has said it does not want to get involved, although it has tried to mediate.