However, Thai Ambassador to the UN Laxanachantorn Laohaphan said Surakiart would not withdraw from the race despite coming in fourth.

Foreign Ministry spokesman Kitti Wasinondh hinted Surakiart's downswing might be coup-related, saying there was not enough time to create understanding with the Security Council prior to the third round of the straw vote.

In Bangkok, Asda Jayanama, former Thai ambassador to the UN, and a fierce critic of Surakiart, urged the ruling Council for Democratic Reform (CDR) to withdraw the deposed deputy premier's candidacy out of concern his refusal would jeopardise the region's chances of getting an Asian to take up the UN top post.

He reminded the Foreign Affairs Committee, recently appointed to advise the ruling military council, that they no longer worked for Surakiart and urged them to advise the generals to withdraw Surakiart's bid before Thailand's international standing became tainted.

Asda, who served as Thai ambassador to the UN for six years before retiring, urged the ruling military council to give consideration to the possibility of supporting former Foreign Minister Surin Pitsuwan.

A diplomatic source told The Nation earlier this week the US was interested in exploring the possibility of Surin being a candidate for the UN top job, citing his experience and background.

Asda said the secrecy of the ballot meant no one knew whether he or she got the necessary approval of all five veto-wielding members of the council.

He added that the results could give South Korea Foreign Minister Ban Ki-moon the momentum he needed to win, or clear the current field for more people to enter the race.

Ban kept his spot as the favourite in the race, the only one among the seven Asian candidates to get the needed majority of votes. Chinese Ambassador to the UN Wang Guangya said Ban received 13 votes in favour, one against and one "no opinion".

Ban slipped slightly from the previous poll, held on September 14, when he received 14 votes in favour and one against.

None of the other six candidates yesterday received the necessary nine favourable votes to make their campaigns viable.

Asda said there was a concern the vote against Ban had come from one of the five permanent Security Council members, which would mean an end to his bid and possibly to those of other Asians, as well, because none appeared to have been able to secure a passing grade.

"Asia could very well see this seat slip away from the region completely," he added. A veto from one of the five permanent members - Britain, China, France, Russia or the United States - could doom a candidate's campaign.

Diplomats generally agree the next secretary-general should come from Asia, because of a tradition that the post rotate among the regions of the world. The last Asian secretary-general was Burma's U Thant, who served from 1961-71.

In the straw vote conducted yesterday, the 15 Security Council members checked one of three boxes for each candidate: "encourage", "discourage" or "no opinion."

In the next Security Council straw poll, set for Monday, the five veto-wielding members of the council will use ballots of a different colour from those of the other 10 non-permanent members.