Maldives Elections Commissioner Fuad Thoufeek said that a second round runoff between former president Mohammad Nasheed and former president Abdul Gayoom's half-brother will take place as scheduled, reported Xinhua.
He insisted that it would be difficult to postpone the vote by 48 hours as demanded by Yameen.
However, since there is back-to-back polling across 200 islands, due to logistical constraints, voting is likely begin at 12 noon local time rather than the customary 7 a.m.
Thoufeek also emphasised that Yameen had not officially notified the Elections Commission of his decision not to take part in the second round vote and expressed hope that he would "change his mind".
"Ballot papers have already been printed and we are working on distributing them to all the polling station. We will hold the second round as scheduled," he stressed.
"If we do not elect a president this weekend from Monday we will not have an elected president and as a country we will face many challenges."
Yameen, who grabbed 29.73 percent of the first round of voting Saturday, told reporters that he is has little confidence in the polling being fair.
Yameen, who was to face former President Mohammad Nasheed, who in turn won the first round of polling with 46.93 percent in a run-off, insisted that he needs at least 48 hours more to iron out issues in the all-important voters list.
Political wrangling over the electoral list has already derailed a previous election Oct 19, which the police blocked at the last minute because the lists were not signed by Yameen and fellow candidate tycoon Gasim Ibrahim.
Gasim, who came in third in the latest round of polls with just 23.34 percent, has agreed to back Yameen in the run-off, the latter noted.
Nasheed has called on the international community to intervene.
The first round of poling Sep 7 that also saw Nasheed emerge as winner was annulled by the Supreme Court after Gasim alleged large scale vote rigging.
With Yameen insisting polling will not take place as planned Sunday, there is greater danger that Maldives will fall into deeper political disarray.
Nasheed has called on the international community to intervene to ensure polling goes ahead as planned.