The Election Commission was obliged by law to seek a court order for the disbandment of the Move Forward Party (MFP), or it could be held in dereliction of its duty, according to the EC chairman.
Ittiporn Boonpracong on Wednesday denied claims that the EC was secretly ordered by another party to persecute the main opposition party.
"What directs the EC is the law. We function in compliance with law... Otherwise, we could be held derelict in doing our duty," he said.
The EC on Tuesday resolved unanimously to ask the Constitutional Court to disband the MFP because the court in January ruled that the party had campaigned for the amendment and revocation of Section 112 of the Criminal Code, known as the lese majeste law. The court judges agreed this was tantamount to attempting to overthrow the constitutional monarchy.
The EC linked the MFP case with Section 92 of the organic law on political parties. The section stipulates that the Constitutional Court can be asked to dissolve any political party that threatens the constitutional monarchy.
On Wednesday the EC chairman said that the EC could also ask the court to suspend the electoral and political rights of MFP figures responsible for the campaign against the lese majeste law. The suspension period was capped at 10 years, he said.
Mr Ittiporn said the EC's official request for the dissolution of the MFP would be ready for submission next week. The EC could also consider if the MFP had violated other laws in relation to the matter.
MFP leader Chaithawat Tulathon said his party would defend itself strongly in submissions to the Constitutional Court.
The party's dissolution would not solve any political problems, he said. To the contrary, it was likely to escalate political conflict.