Around 200 people took part in a rally on Moore Street to support a group of protestors currently occupying buildings central to the 1916 Rising.
Restoration works have stopped on numbers 14 to 17, the site of the last stand by the rebels during the Easter Rising.
It's being turned into a new commemorative centre as part of the centenary celebrations.
However, the group say they've concerns that the work being carried out on the group of buildings will see the demolition of number 13 and numbers 18 and 19 Moore Street - which they say are also of historical importance.
The protestors say they'll occupy the building for as long as it takes for a proper resolution, which will see the restoration of the entire terrace and the surrounding lanes and streets.
Heritage Minister Heather Humphreys said in a statement that she's "very disappointed that any group would attempt to delay these works and jeopardise the project. Furthermore, the occupation of the building poses risks to the individuals involved and the building itself, which is in a very fragile state".
She added; "Nos 13 and 18 and 19 are not part of the National Monument, and are not historically significant. Demolition (of Nos 13 and 18) is necessary to underpin the National Monument, which is an old building built without proper foundations".
"Documentary evidence (Valuation Records 1911-1915, 1915-1925; Thom’s Directory 1915) shows that Nos. 18 and 19 (the former Paris Bakery) were in ruins prior to the 1916 Rising".
Meanwhile, another group, made up of the relatives of those who fought in 1916, are taking a case to the High Court on Monday to try and stop the Moore Street project.
