All household visits are to be banned from Thursday night, it has been confirmed.
There will be exceptions for compassionate grounds and essential reasons like childcare.
Monaghan, Cavan and Donegal are all be moved onto level four coronavirus restrictions from midnight Thursday.
Other counties will remain at level three, but with several new measures also now in place.
The measures announced this evening will remain in place from tomorrow midnight until Tuesday November 10th.
Taoiseach Micheál Martin said the country has reached a difficult point with the coronavirus, and the current infection numbers are just 'too high'.
He said there was a need for an 'immediate escalation' of restrictions in Cavan, Donegal and Monaghan - with level four measures to include the closure of non-essential retail.
The Taoiseach said there are concerns around the full implementation of level three rules - including around household visits.
He also said people should not travel to their workplace 'unless they absolutely have to'.
An exemption which allowed club championship matches to proceed is also now being removed nationwide.
While garden visits are to be banned, up to six people from two households will be able to meet in outdoor public places.
Tánaiste Leo Varadkar has also warned more counties are likely to move to level four restrictions, noting that people shouldn't 'for a second' relax if their counties aren't being moved to tougher restrictions tonight.
The Government has confirmed COVID-19 support schemes announced during yesterday's Budget will be available to businesses impacted by both level three and four restrictions.
Earlier today, Northern Ireland's Executive announced a four-week 'circuit breaker' lockdown aimed at curtailing soaring coronavirus rates.
