Mr Suthep told reporters on Monday that the PDRC will continue protesting at its Lumpini Park rally site until caretaker Prime Minister Yingluck Shinawatra steps down to pave the way for national reform.
"It might take us a month or two to win. If not, we'll carry on protesting," he said.
"In the end, the Thaksin regime must be eradicated, there's no other choice. If a neutral government is set up, no political parties, including the Democrat Party, will be involved. It will comprise only neutral individuals who have no mutual interests in any political party."
Reporters asked Mr Suthep which side of the political divide he believes the military supports. The protest leader argued that the armed forces have said they will stand side-by-side with the nation. He said this implies that they do not want to side with the government.
Asked if another election should be held to elect a new administration to implement national reforms, Mr Suthep replied no. "Pheu Thai will still win if the election is organised under the old regulations and it won't implement the reforms," he said.
Former deputy prime minister Pridiyathorn Devakula meanwhile said he believed the prolonged political stalemate is nearly over.
He said the caretaker government has suffered several major setbacks, including the charter court ruling that its 2-trillion-baht borrowing bill was unconstitutional. The government may not accept the rulings, but the general public does, he said.
"It would be good if the political situation ends in the first half of this year because a new government with full authority can come in to invest in infrastructure. If this goes on, the country's economy, especially the real estate sector, would be hit further," he added.