Ireland has been put under similar lockdown measures to the UK following three more coronavirus-related deaths.
Taoiseach Leo Varadkar said residents should stay home until at least 12 April unless they are buying groceries, attending medical appointments or collecting medication, getting brief exercise or making essential family visits.
Almost all shops will be told to close and all gatherings outside of families will be banned.
Taoiseach Leo Varadkar appealed to those in Ireland to make sacrifices to help each other
Public transport will be available only to essential workers and nobody should travel beyond 2km (1.2 miles) from their homes for any reason, he added.
Those over the age of 70 or with chronic diseases will be told to stay in their homes without exception over the period, which begins at midnight.
Mr Varadkar said: “Freedom was hard won in our country, and it jars with us, to restrict and limit individual liberties, even temporarily. But freedom is not an abstract concept.
“We give it meaning every single day – in the way we live our lives – and in the decisions we take willingly to protect our loved ones.
“So I am asking people to give meaning to our freedom and liberty by agreeing to these restrictions. Restricting how we live our lives so that so that others may live.
“I am asking us for a time, to forego our personal liberties and freedoms for a greater cause.
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“Tonight I am appealing to every man, woman and child in our country to make these sacrifices – not out of self-interest but for each other.
“To begin each day knowing that every single imposition, every inconvenience, every irritation will save lives and help our health service cope.
“The whole world is suffering during this pandemic, and Ireland is no different.
“What happens now is up to each one of us.”
The measures come after three more deaths thought to be as a result of COVID-19, the respiratory illness caused by coronavirus. One of the victims was a healthcare worker.
According to data compiled by US university Johns Hopkins, there are 2,121 coronavirus cases in Ireland, with 22 deaths recorded.
Schools had already been closed, along with universities, pubs and most non-essential shops but, despite this, Mr Varadkar has previously warned that the country’s intensive care units would be at capacity within a few days.
Ireland’s chief medical officer, Tony Holohan, said the earlier rules were working and that the number of new cases was slowing. However, he added that this did not mean that the worst was over.
“We think we see signs that are encouraging us, that this is helping, but we think we need to go further,” he said.
“We think in the early course of this infection, with the support that we have had from the public, that with these additional strengthening measures, we can drive the infection back out of the community and more into households.”
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Sky’s senior Ireland correspondent David Blevins said: “Leo Varadkar chose his words carefully, acknowledging the value Ireland places on its freedom and asking the population to give that freedom meaning by saving lives.
“It is difficult, if not impossible, to remember any previous taoiseach making a statement of such significance. In the space of 10 days, he has made what many would consider to be the two most defining addresses of his political career.
“It is also worth noting that he made them as caretaker taoiseach because the Irish parliament has not yet reached agreement on the formation of a coalition government following the election at the beginning of February,” he added.