Former protest leader Suthep Thaugsuban has reaffirmed his demand that national reforms must take place before elections.
He said major changes must be achieved no matter how long the process takes.
Despite his staunch stance, Mr Suthep promised he or his supporters would not stage more street demonstrations that could lead to fresh political conflicts and unrest.
He made the remarks Thursday during the launch of the Muan Maha Prachachon for Reforms Foundation, which succeeds the defunct People's Democratic Reform Committee (PDRC).
Muan Maha Prachachon (Great Mass of the People) describes former PDRC supporters as a mass, collective force.
Benjarong Suwankiri, head of TMB Analytics, an economic analysis unit of TMB Bank, said the political landscape was likely to change now Mr Suthep has left the monkhood.
Over the past year, the coup has brought a period of political stability. But any new round of political rallies could cause jitters among foreign investors, Mr Benjarong said.
"We need to see what the foundation's next move will be," he said.
"But what is more worrying is the continuity of this government's policy. It has set out reform plans for the next five to 10 years, but there is no guarantee they will be implemented by the next administration," he said.
Mr Suthep said he wanted to see the military government accomplish its reform plans before elections are held, no matter how long the process takes.
He said the foundation supports the reforms initiated by the government.
But if the government's reforms do not move in the right direction, the foundation will offer its views and suggestions peacefully, rather than by staging demonstrations, Mr Suthep said.
"There will be no more rallies or protests. We will not storm anyone's offices," he said.
"We will let the public know how the government's opinion differs from what we think. Whether right or wrong, the people will decide," the former PDRC leader said, adding the foundation is ready to work with all groups for the benefit of the country.
Mr Suthep said the reforms were important. Change in other areas will be futile if the "same old politicians" return to power after the next general election.
The PDRC launched a "reform before election" campaign as the group ramped up protests seeking the ouster of the former caretaker government led by Yingluck Shinawatra.
The Yingluck administration was forced to call the Feb 2, 2014 election in response, hoping the poll would ease the mounting pressure on it.
The PDRC argued reforms must happen before the polls. If the elections happened without reforms, corruption would only continue, he said.
At Thursday's press conference, Mr Suthep, accompanied by ex-Democrat MPs who sit on the foundation's committee, made it clear he would not return to politics.
The former Democrat deputy leader also insisted the foundation has no affiliation with the Democrats and that foundation members, who are former Democrat MPs, will not return to the party.
Mr Suthep led the PDRC's anti-government protests against Yingluck Shinawatra that culminated in last year's coup.
Shortly after the coup, he turned his back on politics and was ordained as a monk at Wat Thasai in tambon Tha Thong Mai of Surat Thani's Kanchanadit district. He left the monkhood on Tuesday.
Foundation deputy chairman Sathit Wongnongtoey said it is not a political group, even though its founders were former politicians.
The military sent soldiers to record the foundation's press conference.
Col Burin Thongprapai, an officer of the Judge Advocate-General's Department, said the foundation had sought permission to hold the press conference from the 1st Army chief and had promised not to discuss politics.
The Pheu Thai Party's former education minister Chaturon Chaisaeng said the junta should now permit other groups to hold press conferences in the same manner as Mr Suthep did to avoid criticism of double standards.
Asked to comment on the timing of Mr Suthep's move, Mr Charuton said the charter drafters will complete their new constitution soon and submit it to the National Reform Council (NRC) to vote on it.
If the NRC approves the draft, the document will be put to a referendum.
But if the NRC rejects the draft charter, the charter-drafting process will start anew, which would further delay the poll, Mr Chaturon said.