Ethiopia's ruling party has won an overwhelming majority in a landmark parliamentary poll, the electoral board said Saturday, ensuring a new five-year term for Prime Minister Abiy Ahmed.

His Prosperity Party won more than 400 seats out of a total of 436 in the election held on June 21, according to results issued by the National Election Board of Ethiopia (NEBE) at a gathering in Addis Ababa.

Documents from the NEBE showed the PP winning 421 seats but it then said there would have to be a re-run election in 10 constituencies and a recount in three more.

The poll was held in the midst of a gruelling conflict in Ethiopia's northern Tigray region that has battered Abiy's global reputation and raised fears of widespread famine.

Voting did not take place in about one fifth of the country's 547 constituencies. A second batch of voting is due to take place on September 6 in many of those left out, but no date has been set for Tigray.