The Election Commission (EC) expects it will take two weeks to establish whether a video call made by ex-premier Thaksin Shinawatra to Pheu Thai Party members likely broke the law on political parties, EC secretary-general Jarungvith Phumma said Monday.
He said a working group was checking the facts in the case and gathering information before deciding on a larger probe.
The results will be reported to the election commissioners today, he added.
At this early stage, the EC will not invite Pheu Thai to give any statements, he said.
Thaksin's video call last week to a number of former Pheu Thai MPs in the northeastern province fits the definition of "direct or indirect influence by an outsider on a party", which is banned under sections 28 and 29 of the organic law on political parties, Pol Col Jarungvith said over the weekend.
A party that allows itself to be dominated or influenced by an outsider is liable to be dissolved under that law.
A video clip of Thaksin, reportedly shot in London on Thursday, shows him telling the former Pheu Thai MPs he was confident the party would win in all constituencies in the Northeast in the next election, expected in February.
Thaksin was also quoted as saying, apparently in a sarcastic tone, that he would Tweet to thank those who defected from Pheu Thai because they had sacrificed their chances of success in favour of new faces.
Mr Jarungvith said Monday that the EC was reviewing what Thaksin discussed with the Pheu Thai members and was also keeping a close eye on whether the former premier's words were being adopted as part of the party's guidelines or policy.
However, any influence Thaksin might have on the party would be conspicuous once the political activities ban is lifted and Pheu Thai is able to implement its policies.
The EC said it would check to see if the party was toeing Thaksin's line.
Deputy Prime Minister Prawit Wongsuwon declined to comment on the video call.
Nattawut Saikuar, a core leader of the United Front for Democracy against Dictatorship (UDD), advised the EC to monitor other parties for legal violations.
Pheu Thai, he said, has been the victim of a poaching campaign that has seen a rival party urge its former MPs to defect.
He urged the EC to look closely at the Phalang Pracharat Party to find out who its real members are -- especially those not registered with the EC. Such "members" are dictating the party's moves, which far exceeds their mandate of exerting influence, Mr Nattawut said.