The People's Democratic Party, which won just two seats to a new 47-seat national assembly, said it will ask Bhutan's Election Commission to look into possible illegal last-minute campaigning by the winning party.

'We feel that in a number of constituencies the balance may have been tilted due to last-minute campaigning,' Mr Tashi Tsering, spokesman for the opposition People's Democratic Party told AFP from Thimpu by telephone on Sunday.

Bhutan gave a stunning landslide victory in Monday's polls to the Druk Phuensum Tshogpa (DPT) or Bhutan United Party, led by ex-premier Jigmi Thinley, surprising analysts who had predicted a close race.

'We knew elections were going to be very competitive,' said Mr Tsering. 'We knew there was a possibility of losing, but not by the margin we experienced.'

The party told the state-run Kuensel newspaper on Saturday that it had received reports from several districts suggesting that campaigning took place in the 48 hours up to voting on March 24 in violation of election regulations.

Its two winning candidates resigned their seats in protest on Friday, leaving the national assembly with no opposition, the Kuensel reported.

Mr Tsering added that the party was not trying to overturn the election results, 'but to ensure that such things - if they occurred - do not happen again in the future.' The opposition party has until April 4 to file a petition.

The head of Bhutan's Election Commission, Kunzang Wangdi, said on Sunday that his office had yet to receive any complaints but added that the polls were viewed as 'a free and fair election by the media, by everybody.'

Some 42 international observers monitored the landmark vote proposed by Bhutan's royals to peacefully transform the tiny Buddhist nation, wedged between massive neighbours India and China, into a constitutional monarchy.

The EU and the United States hailed the elections this week and said they met international standards. -- AFP