The National Anti-Counter Corruption Commission (NACC) has pledged to wrap up at least 15 corruption cases by the end of next year.
NACC secretary-general Warawit Sukboon said several of these cases are highly controversial such as the 2013 floodwater management affair, government-to-government rice-pledging deals, temple fund embezzlement, the Rolls-Royce bribery scandal, and the Uea Arthorn Housing project.
The others include PTT's investment in palm oil plantations in Indonesia, the procurement of fake bomb detectors, the construction of a futsal stadium, and cases of illegal issuance of land title deeds in forest reserves in Phuket and Nakhon Ratchasima.
"We've made significant progress in several of these cases and some are 80-90% completed," he said at a press conference marking the 20th anniversary of the Office of the NACC.
Mr Warawit said that from 2016 to the present, the number of cases pending has fallen from 85.24% to 75.55%.
"The NACC does not let any case go unsolved, no matter when it took place," he said.
On the Rolls-Royce bribery scandal, he said the NACC has decided to formally accuse 10 out of 26 individuals linked to the scheme, but noted that none of them are politicians.
The probe was launched after Rolls-Royce admitted misconduct to the British Serious Fraud Office in January 2017 that it gave bribes to "agents of the state of Thailand and employees of THAI Airways" to influence purchases of its engine from 1991-2005.
The bribes, reaching upwards of 1.25 billion baht, were reportedly paid to secure THAI's purchase of three lots of Rolls-Royce Trent 800 turbofan engines.
Mr Warawit said that if any evidence comes to light linking politicians to the scandal, they too will be investigated.