Former election commissioner Somchai Srisutthiyakorn has urged the Election Commission (EC) to rev up moves to probe a recent fund-raising event organised by the Palang Pracharath Party (PPRP).
Mr Somchai, now a member of the Democrat Party, said he will give the poll-organising agency seven days to take action or he will file suit against the EC for dereliction of duty under Section 157 of the Criminal Code.
The EC must "take a proactive approach" by asking the PPRP for details regarding the guests attending the event and footage from surveillance cameras at the event, Mr Somchai said.
"The public want to see the EC work proactively and enforce compliance with the law rather than waiting 30 days for a political party to submit details of the event," Mr Somchai said.
The EC must investigate if the cabinet ministers who are at the helm of the PPRP used their positions to solicit funds for the party, which is prohibited by the law governing political parties, Mr Somchai said.
The PPRP consists of Industry Minister Uttama Savanayana as its leader, Science and Technology Minister Suvit Maesincee as deputy leader, Commerce Minister Sontirat Sontijirawong as its secretary-general, while PM's Office Minister Kobsak Pootrakool is the party's spokesman.
EC secretary-general Jarungvith Phumma previously said the PPRP must submit a report on the fund-raising banquet it held last Wednesday, including those who donated more than 100,000 baht, within 30 days.
Pol Col Jarungvith said the poll agency will look into the details after the report is filed but it can launch a preliminary probe if a complaint is made first.
He also played down media reports that some government agencies contributed at the event in which the party claimed to have raised about 600 million baht.
He said state agencies were required to follow strict rules and their spending was subject to audit.
Cap Thammanat Prompao, member of the PPRP's panel for the election strategy in the North, on Sunday said that he had no details of how much money was raised at the event, but he said it was a substantial sum which "demonstrates supporters' confidence in the party as an alternative for Thais".
The PPRP claimed it raised 600 million baht from some 200 tables with its Chinese-style feast themed "United Thailand", in which each table cost three million baht.
The PPRP's fund-raising banquet has sparked criticism from political parties and calls for the EC and the National Anti-Corruption Commission (NACC) to investigate it for transparency following reports that government officials and political office holders contributed to the campaign.
Under Section 76 of the organic law governing political parties, government agencies, state enterprises or any agency in which the state is a major shareholder are barred from making political donations or taking part in such activities.
Section 73 prohibits political office holders from using their positions to solicit funds for political parties or candidates. However, political office-holders are not barred from joining fund-raising activities.