"Once electoral complaints have been adjudicated in accordance with the law, I urge the candidates and their supporters to accept the outcome," Xinhua news agency quoted Tadamichi Yamamoto, the UN secretary-general's Special Representative for Afghanistan, as saying on Monday.
"When the election is completed with credibility, it will become a milestone in the history of establishing a representative political system of the country," he told the Security Council.
Yamamoto also called on all stakeholders to enable the electoral institutions to exercise their responsibilities in full, including by addressing all complaints through the appropriate legal and institutional channels.
The Afghan presidential election was held as scheduled on September 28. Preliminary results, which were expected by October 19, are yet to be announced.
The main contest is between President Ashraf Ghani, who is seeking a second term, and his Chief Executive Abdullah Abdullah.
The primary reason for the delay is to ensure that the electoral process is as transparent and credible as possible even at the sacrifice of time, explained Yamamoto, who is also leading the UN Assistance Mission in Afghanistan.
From a technical perspective, the presidential election this year has improved considerably on past polls in Afghanistan, with much greater transparency, he said.
The use of biometric voter verification devices seemed largely effective in detecting and deterring fraud, and several new check mechanisms throughout the process have enabled the electoral management bodies to detect and eliminate multiple and fraudulent votes.
Candidates and other political stakeholders have had far greater access to information than in previous elections, he said.
Nevertheless, this electoral process has not been without problems, said Yamamoto.
Some candidates and their supporters have expressed concerns regarding the technical aspects of the process and the lack of public information.
There have been numerous exchanges between the electoral management bodies and candidates both orally and in writing. This process entailed the blockage of audit and recount in seven provinces by supporters of some candidates.
The blockage added to the delay in the announcement of preliminary results.
However, the process finally resulted in the resumption of audit and recount in the remaining seven provinces on Sunday.
"Now we are expecting to hear the preliminary results soon," Yamamoto added.
( With inputs from IANS )