It is too early to say if Dublin will move out of Level Three restrictions but the Taoiseach says that the next 10 days will be crucial.
Speaking at the Oliver Bond complex in Dublin, the site of a party last week which is being investigated by Gardaí, Mícheál Martin said that it was clear that behaviour has to change.
"First of all, I would say that there is an absolute need for people to reduce their social contacts. And then the next 10 days will be critical.
"We are aware of counties like Donegal and others, where the numbers are going in the wrong direction, but also I've been speaking to the CMO and we are concerned about large urban areas and cities and particularly Waterford, Cork, Limerick and Galway.
"The situations for those cities is critical over the next 10 days and behaviour has to change quite frankly. People would have to reduce their social contacts, so quickly in the wrong direction.
"And it's imperative that action is taken now both collectively and as individuals. And in those particular locations."
Health officials are meeting today to decide if further measures are needed to stop the virus spreading.
The Taoiseach said that the capital was still in the first week of restrictions and it was too early to say if further restrictions will be needed.
He said that the government would examine issues around social welfare in the Budget.