The only way to end violence in Northern Ireland is through the political process, Stormont's First Minister said.
Peter Robinson condemned those responsible for injuring dozens of police officers and costing the local economy millions but said protesters had become alienated.
"There are political issues and people that feel disengaged and people that feel if we are trying to build a shared future they are not getting their share," he said.
Northern Ireland's most senior police officer has praised his "courageous" colleagues after sectarian rioting left 29 members of the force injured.
Police Service of Northern Ireland chief constable Matt Baggott said the vast majority of people were grateful for their efforts as fireworks, bricks and other missiles rained down on them.
Violence broke out in east Belfast between republicans and loyalists returning from a protest at Belfast City Hall over a council decision to restrict the flying of the Union flag there.
The chief constable said: "This was a difficult operation dealing with a large number of people determined to cause disorder and violence. My colleagues brought the situation under control with exceptional courage and professionalism."
Trouble erupted on Saturday afternoon on the Albertbridge Road near the nationalist Short Strand and police separated the opposing factions.
As the loyalists approached the Short Strand there was violence across the interface with missiles being thrown by rival factions, which resulted in a number of properties being damaged in the Short Strand.
Police used water cannons and fired six baton rounds as they forced the two sides apart. Four officers were taken to hospital, two have been discharged.