The relatives of the 1916 leaders say they'll go to court unless the government agrees to preserve the entire Moore Street area.
The families say the whole Moore Street terrace - the final headquarters of the 1916 leaders - needs to be saved from redevelopment.
Currently only four buildings on the street are listed as a national monument and are safe from destruction.
James Connolly-Heron, the great-grandson of James Connolly, says there's an urgent need to save the rest of the terrace from being turned into a shopping centre:
