Level 5 restrictions are being re-imposed for 'at least' one month.
Gyms and non-essential retail will be shut from close of business tomorrow, while no visitors will be allowed to private homes from this evening.
Six guests will be permitted to attend weddings, with 10 people allowed at funerals.
The Taoiseach has also revealed schools will remain closed until January 11th in an address this evening.
The government has published the full list of restrictions here.