The chairmen of local election offices in Songkhla's seven constituencies yesterday boycotted the registration of additional MP candidates for the repeat vote in defiance of the Election Commission's (EC) ruling on the matter.

The two-day registration is expected to be completed today in spite of the boycott. The repeat vote is scheduled for Sunday.

"The EC instructed us to hold the additional candidacy registration at short notice, making it impossible to implement," Kitnan Phet-udom, chairman of Constituency 7 Election Office, said.

The EC relayed its instructions late on Tuesday night and expected local election offices to comply the next morning without any preparation, Kitnan said, adding that he and his colleagues were tied up with the supervision of the senatorial race.

Instead of doing a half-baked job, all seven chairmen decided not to get involved with the additional candidacy registration, he said.

Songkhla Election Office director Paitoon Jehae said the seven chairmen had notified him of their boycott. "I decided to take over the seven chairmen's responsibilities in order to facilitate the registration process for additional candidates in Songkhla," Paitoon said.

Three of the seven chairmen have tendered their resignations in a gesture of protest over Paitoon's intervention, while the other four said they will resign after the completion of the repeat vote.

Democrat Party deputy secretary-general Thaworn Senniam said the EC had no mandate to accept additional candidacy applications.

The bottom line was the EC had conspired with two small parties, Prachakorn Thai and Khon Kho Plod Nee, to help lone Thai Rak Thai Party candidates to overcome the 20-per-cent rule, Thaworn said.

Under election law, candidates who run unopposed must achieve 20 per cent of eligible votes to validate the election outcome.

Thaworn said the EC had erred in allowing constituency hopping in the repeat vote for defeated candidates from the first round of balloting.

"The Supreme Court ruled against the EC and cancelled the planned repeat vote for two defeated candidates from Songkhla," he said.

Thai Rak Thai Party deputy leader Pongthep Thepkanchana said he had no opinion about the repeat vote in Songkhla.

"The conflicting views on how to manage the repeat vote are internal affairs for the EC to resolve without the involvement of the ruling party," he said.

As he understood it, he said, the EC was obliged to keep repeating the vote, regardless how many rounds, until it can fill 400 House seats.

He added that his party's candidates were bound to campaign until they passed the 20-per-cent rule.

A group of 1,000 Songkhla residents rallied at the candidacy registration centre, protesting against the EC for attempting to validate the ruling party's candidates although local voters rejected them on April 2.

Despite the protest, eight candidates from smaller political parties did register in seven Songkhla constituencies where otherwise Thai Rak Thai candidates would have run unopposed in the second round of voting on Sunday.

The protesters dispersed from the local Border Patrol Police bureau at about 5pm.