Irish premier Leo Varadkar has condemned the actions of a republican group that paraded down Dublin’s O’Connell Street after the murder of Lyra McKee.

Mr Varadkar said the march, by a group associated with the so-called New IRA, had dishonoured the Irish national flag.

The Taoiseach added that it was an “insult” to the Irish, as people across the island mourned the journalist and author.

Ms McKee, 29, died after she was shot in the head by a member of the New IRA during a Londonderry riot on Thursday.

About 150 members of the Saoradh group held a march in military colours wearing berets and sunglasses in the capital on Saturday.

“The actions by Saoradh in Dublin this weekend are beneath contempt,” Mr Varadkar said.

“People North and South are mourning the death of a brave campaigner and journalist, Lyra McKee.”

He added: “On Sunday we marked the heroes of 1916 who put Ireland on the path to democracy.

“Others like Saoradh want to return Ireland to a violent and troubled past. We can never allow this to happen. Saoradh should apologise for their actions this weekend.”

The Taoiseach attended a commemoration outside the GPO on Dublin’s O’Connell Street on Sunday afternoon to mark the 103rd anniversary of the Easter Rising.

Irish president Michael D Higgins laid a wreath in memory of all those who died in the rebellion.

The proclamation of the Irish republic was read out by a member of the country’s defence forces.

Mr Varadkar said the right to assemble and march was won by the men and women of 1916, who fought for the freedom and democracy that is enjoyed today.

He said Saoradh had “dishonoured their legacy and memory”.

“It was an insult to the Irish people,” he added.

He said the words of the proclamation had resonated with him as they were read outside the GPO.

“The proclamation condemns those who, in the name of Ireland, would dishonour the flag through cowardice or inhumanity,” he said.

“Those involved in dissident activity should reflect on those words.”

The Irish justice minister also condemned the display, describing it as “very disturbing”.

“I know that all right-thinking members of the public are sickened at the sight of a small number of people in paramilitary uniforms, particularly after the horrific killing of a young journalist, Lyra McKee, in Derry on Thursday night,” Charlie Flanagan said.

“These demonstrators do not represent the views of the Irish people, who have been united for many decades in rejecting paramilitarism and are rightly revulsed at this display.”

Mr Flanagan said the Garda had policed the Saoradh event on Saturday “appropriately and with restraint in the circumstances”.