As Abdullah Abdullah, the challenger to sitting President Hamid Karzai, announced Sunday to boycott the runoff. Observers cautioned of bleak impact if the procedure was held with lone contender.

"Definitely Afghanistan would have a weak and inefficient government if the second round election is held with one candidate, " Qasim Akhgar, a political analyst and human right activist, told Xinhua.

Abdullah, who secured 28 percent of nearly 6 million votes cast in Aug. 20 fraud-marred presidential election against Hamid Karzai who bagged over 54 percent in the preliminary result announced in mid-September, vowed not to accept the result unless the complaints are examined.

The election monitoring body -- Election Complaints Commission (ECC) -- a five-member UN-backed panel, after invalidating 210 polling stations out of some 27,000, lowered Karzai's vote bellow 50 percent, prompting IEC to hold runoff on November 7 between two the top contenders.

Welcoming the step, what he described as "to have fair second round presidential polls," Abdullah has put conditions which include sacking election body's commissioner Azizullah Ludin and suspension of three ministers for Interior, Education and Frontiers.

However, President Karzai rejected the demand, stressing that the officials have done nothing illegal to remove them.

"Since the election commission is not an independent body we cannot expect to have fair result and the outcome of the runoff would be more fraud-tainted than the first round, so I have decided not to participate in it," Abdullah told a gathering of hundreds of his supporters.

"Although, it is a tough decision, I have taken it in consultation with the people for the larger interest of the nation," Abdullah emphasized.

Meantime, eminent analyst Wahid Mujda opined that holding second round election with the participation of only one candidate is more like referendum than election and any vote to Karzai ultimately makes him the winner.

However, he cautioned that credibility of the administration which comes to power through voting in one contender would be questioned at home and aboard.

"No doubt, if Karzai is the sole contender in the runoff the legitimacy of his government will be questioned and the problems of the country especially the security problems will be increased," Mujda told Xinhua.

When his comment was sought towards the remarks of U.S. Secretary of State Hillary Clinton in which she said that Abdullah ' s boycott will not de-legitimize the runoff, Mujda observed that having support at home is vital for a government.

"At the eyes of international community it is legitimate as it has ambassadors and embassies. But it is essential that election must be held between two candidates and the winner can form legitimate government," the observer told Xinhua.

He was also of the view that some countries would review their assistance to Afghanistan keeping in mind that some countries have criticized the administration over its failure to check corruption.

Corroborating the notion, another observer and journalist Nazari Pariani held the view that legitimacy of any administration that comes to power through one-man election would be questioned.

"Security problems will be increased, Afghanistan will be isolated and the contribution of the international community for the reconstruction process of the war-torn country would be affected if Karzai remains in power for the second term through one-man election," Pariani said.