Labour leader Robert Abela has not denied allegations that prisoners who are ineligible to vote did so anyway.
Answering questions on Tuesday morning, Abela seemed to pour cold water on the claims, saying the electoral process included representatives of both main parties.
However he would not outright deny any errors or foul play, nor would he say whether the process should start afresh.
“That part of the electoral process is regulated by the electoral commission which has representatives of both political parties. The electoral commission will exercise its duty according to law,” he said.
The Nationalist Party has called on the Electoral Commission to cancel voting held last Saturday at the prisons as part of the general election, saying several prisoners were not eligible to vote.
According to electoral law, anyone serving a prison sentence of longer than 12 months is not allowed to vote.
35 illegal votes suspected
But the PN says that rule was breached this past weekend, when several ineligible prisoners cast their vote during an early voting process for Corradino Correctional Facility inmates.
Sources have told Times of Malta that around 35 prisoners who should not have voted did so.
The PN has claimed that problems were caused by court registrars who failed to notify the Electoral Commission about convicts ineligible to vote.
Court registrars in Malta and Gozo are obliged to notify the electoral commission every month with the names of prison inmates sentenced for more than a year in jail.
The Electoral Commission has said that it relies on public officials to provide it with up-to-date information about voters and their eligibility and that it could not stop a person listed on the electoral register from casting their vote.
The PN has reserved the right to take the matter to the Constitutional Court.