To try and forge an alliance in preparation for forming a government ahead of an election would be undemocratic, says Democrat Party leader Jurin Laksanawisit.
Mr Jurin insisted that the Democrats will only decide whether to join a government after the election results are known.
"We need to let people decide first, and that's the principle our party stands by," Mr Jurin said.
He added that any pre-election pledge to either ally or not with another party is against democracy as the people's mandate has not been passed.
"Elections are requisite for democracy," said the Democrat leader.
His remarks follow the ruling Palang Pracharath Party's (PPRP) insistence that it would never form a government with Pheu Thai and the Move Forward Party (MFP) in it.
Pheu Thai and the MFP have also said they will not be in the same government as the PPRP.
Mr Jurin said the Democrats would avoid other parties' internal affairs.
Ratifying business
The Move Forward Party (MFP) will ratify the Rome Statute to open a way for the International Criminal Court (ICC) to look into the 2010 crackdown on red-shirt protesters if the party assumes power in the next government, said Piyabutr Saengkanokkul, a key assistant in the MFP poll campaign.
The Rome Statute, which came into force on July 1, 2002, is used to prosecute the most serious crimes of international concern and to end impunity.
Mr Piyabutr said the MFP had formulated part of its election manifesto on the ICC looking into the security forces' dispersal actions at the Kok Wua and Ratchaprasong intersections during the Abhisit Vejjajiva administration.
A number of deaths on both sides were reported.
Information on these events was provided by a red-shirt committee headed by Tida Thavornseth and handed to the MFP in February.
Mr Piyabutr, also secretary-general of the Progressive Movement, which retains close ties to the MFP, said MFP leader Pita Limjaroenrat has announced the party would work toward ratifying the statute if it becomes the next government.
The red shirts' quest for the truth in the dispersal incidents was intended to shed light on what happened, although some of those believed to be responsible for the bloodshed not only went unpunished but were given political posts in subsequent governments.
The MFP has also promised to push for a referendum to rewrite the constitution within 100 days of Mr Pita becoming premier.
PPRP trouble
An investigation is being sought into the ruling Palang Pracharath Party (PPRP) over a recent campaign speech referencing the monarchy.
Srisuwan Janya of the Association for the Protection of the Constitution on Tuesday petitioned the Election Commission (EC) to probe the PPRP over a speech delivered in Huay Krachao district of Kanchanaburi on April 6.
Mr Srisuwan said that during the campaign speech, a party MP candidate told supporters that the opening of the three underground water projects -- one in Lao Khwan district and two others in Huay Krachao district -- was presided over by His Majesty the King.
They are three of 15 such projects around the country.
The three projects show the care that Deputy Prime Minister Prawit Wongsuwon, also PPRP leader, has towards the area's residents, the MP candidate said.
The candidate added Gen Prawit had ordered related state agencies to oversee and maintain the projects.
According to Mr Srisuwan, the speech may constitute a breach of the EC regulation prohibiting a party MP candidate or anyone else from referring to the monarchy while canvassing votes.
