Caretaker senators open a House session yesterday to select a panel of 22 members to check the background of nominees for the new Election Commission.

Withaya, who sometimes supports government policies in interviews with the media, described Kaewsan's supporters as disgusting. He said he felt uneasy that the People's Alliance for Democracy (PAD) had tried to force senators to vote for Kaewsan and Nam Yimyaem by saying if they did not, it would mean there was a bloc vote in the Senate.

"I feel sorry that this is being said, as it insults senators as dumb people," he said.

Withaya said he had intended to vote for Kaewsan and Nam but changed his mind, saying the Election Commission (EC) had to be clearly neutral.

"But Kaewsan once took to the PAD's stage to rally against the government so he is not impartial. Actually I am disgusted by his [PAD] supporters, so I won't vote for him," he said, adding it was his decision alone.

PAD spokesman Suriyasai Katasila said Withaya's stance showed his true colours as a pro-government senator.

He said Withaya was disappointed with Kaewsan because Kaewsan criticised caretaker Prime Minister Thaksin Shinawatra.

"I don't think Withaya has the right to talk about 'neutral' because people think he is a government spokesman in the Upper House," he said, noting that Withaya's role in the past appeared to support the government.

Suriyasai said the PAD had given no support to any particular candidate of the 10 chosen by the Supreme Court for the Senate to scrutinise. But in principle the EC must be honest, free from politics and carry the moral high ground.

"It is Kaewsan's right to take to the PAD stage and give information to the people. In fact he should be appreciated for it," he said.

Outgoing Senator Jon Ung-pakorn, who expressed support for Kaewsan, said he thought Withaya had a hidden agenda in objecting to Kaewsan.

He said it was not appropriate for Withaya to express his bias at a time when the media was presenting news about the Thai Rak Thai Party trying to block Kaewsan and Nam, both of whom had played it straight when dealing with probes into government schemes.