DUBLIN (REUTERS) - The Irish government on Friday (Dec 17) ordered bars and restaurants to close at 8pm and reduced the capacity in all public events in a bid to curb the spread of the Omicron Covid-19 variant.

Irish Prime Minister Micheal Martin said the measures, which will run for six weeks from Sunday (Dec 19), are necessary because the Omicron variant is likely to bring a level of infections "far in excess of anything that we have seen to date".

"There needs to be a very strong and immediate reduction in contacts between people in order to prevent Omicron overwhelming us," said Mr Martin in a televised address.

Ireland's Covid-19 case numbers have eased in recent days, but the government has said it expects a surge of infections as Omicron takes over.

Omicron represented 35 per cent of cases reported in Ireland on Friday, up from 14 per cent on Tuesday, health officials said.

Some parts of neighbouring Britain have reported Omicron case numbers doubling every two days.

A total of 90 per cent of Irish adults have been vaccinated and around one-third of those have also received a booster dose.

Friday's measures were introduced despite vocal opposition by the hospitality sector and a number of lawmakers in the parties of the ruling coalition, who said the move would encourage gatherings that are less safe in private homes.

Under the new rules, indoor events should be limited to 50 per cent of venue capacity or 1,000 people, whichever is lower. Outdoor events should be 50 per cent capacity with no more than 5,000 people.

All people arriving into the country will be required to have either an antigen or polymerase chain reaction Covid-19 test, depending on whether they are vaccinated or not.