A commission investigating disputed presidential and legislative elections in Haiti says the October vote was "stained by irregularities".
But it has recommended that a second round run-off should go ahead as planned on 17 January.
The people of Haiti are choosing a president to succeed Michel Martelly.
Mr Martelly postponed the run-off vote that was due to be held on 27 December after street protests against fraud in the first round turned violent.
President Martelly is constitutionally barred from seeking re-election.
The candidate he backed, banana exporter Jovenel Moise, won 33% of the vote in the first round on 25 October.
In the run-off, he will face ex-state construction company head Jude Celestin, who came second with 25%.
The opposition alleged widespread fraud in the presidential and legislative vote in October.
The commission assigned last month to look into the allegations said there were widespread irregularities.
It recommended legal action against poll workers and other people involved in fraud, the Associated Press news agency reported.
Whoever wins will face a daunting task when taking over from Mr Martelly in February. Haiti is the poorest nation in the Americas.
Since it was devastated by an earthquake in 2010, the country has relied largely on international donations and foreign aid from the United States and other countries.