Sri Lanka's has set July 31 as the date for advance voting for persons under quarantine, National Elections Commission Chairman Mahinda Deshapriya said on Sunday ahead of the August 5 vote.

Over 16 million voters are registered to vote on August 5 to elect a 225-member parliament for a 5-year term.

The election commission has been struggling to make arrangements for a free and fair poll due to the health risks caused by the COVID-19 pandemic.

"The pandemic has forced the election authorities to set an advance polling day for those under quarantine," Deshapriya said.

"Now those under quarantine would be allowed to vote on July 31," he said.

Deshapriya said the identities of the voters under home quarantine would not be revealed to the media.