The government is preparing to invoke the election law to punish the People's Alliance for Democracy (PAD) if it holds an anti-Thaksin rally during the lead-up to the new election, caretaker Interior Minister Kongsak Wantana said yesterday.

"The electoral rules cover the period between August 24 and October 15 and the PAD must stop activities seen as opposing or crediting a candidate or a party," Kongsak said.

He reminded police to arrest anti-Thaksin campaigners found violating the election law.

But Thammasat University's law lecturer Prinya Thewana-ruemitkul said Kongsak might have misunderstood the legal provisions.

"The election law bans the framing of parties or candidates with the malicious intent to sway votes but it does not prohibit the voicing of critical views," he said.

Prinya said political activists were sanctioned by relevant provisions to raise constructive criticism of the government or to convince voters on how they should cast their ballots.

An Election Commission official said the ban against attempts to convince voters not to vote for a particular candidate would be enforced after the completion of candidacy registration process next month.

Anti-Thaksin campaigner Sangsit Piriyarangsan said he would organise a mass rally on September 9 to oppose conflicts of interest and corruption.

"If the Interior Ministry or police try to disrupt the rally, then I will file the administrative lawsuit for abuse of power to block free speech as guaranteed by the Constitution," he said.

He said the election law applied to political parties and electoral candidates but not non-partisan activities.

Meanwhile, It is unlikely the Senate will be able to choose the new election commissioners by the Thursday deadline, according to caretaker Senate Speaker Suchon Chaleekrua.

He said it was probable the Senate would have to approach the Cabinet for a Royal Decree convening another special session.

That could sit in the second or third week of next month, he said.

It appeared the full Senate would be unable to vote on the final five new commissioners by Thursday.

That was when the current special session expired.

A Senate special committee disclosed it could not complete vetting the 10 nominees for five vacant Election Commission (EC) seats in time for a vote on Wednesday.

Sunthorn Chindain, chairman of the special committee, said the task could not be completed in time because two sub-committees had yet to interview some nominees about allegations made against them.

Once the sub-panels were finished the special committee would consider their reports.

Its secretary, Senator Wallop Tangkhananurak, said the panel hoped to consider those reports on Friday.