The Union flag was flying over Belfast City Hall this morning to mark the Duchess of Cambridge's 31st birthday.

A special meeting of unionist representatives in Northern Ireland has been called in a bid to end loyalist unrest over a decision to only raise the emblem on 18 designated days.

Loyalists pelted police with bottles and stones in a new outbreak of trouble in East Belfast last night amid warnings that potential business investors are turning away from the city because of the street violence.

With riot police again facing hundreds of masked men around the lower Newtownards Road area, there is no sign of a halt to the protests.

Fireworks, rocks, golf balls and petrol bombs were thrown at police lines on the sixth consecutive night of violence in the confined flashpoint area of the city.

Northern Ireland First Minister Peter Robinson confirmed that representatives of the various unionist parties will meet at Stormont tomorrow to discuss the trouble, but leaders centrally involved in the protests who are threatening to take their campaign on to the streets of Dublin on Saturday have pledged they want no part in the discussions.

The Confederation of British Industry (CBI) claimed jobs would be lost and shops shut unless there is an immediate end to the trouble.

CBI Northern Ireland director Nigel Smyth warned: "We are already aware of investors who have lost interest because of these disruptions."

The unrest has continued intermittently since Belfast City Council's decision last month to reduce the number of days the flag flies to 18. A total of 66 officers have been hurt and 104 arrests made since the protests started a month ago.

Mr Smyth added: "The violence and disruptive actions of those involved in the street protests is having a detrimental impact on local businesses, as well as damaging prospective tourism investment."

Mr Robinson, who will head up Thursday's Forum with the Ulster Unionist leader Mike Nesbitt, admitted there was considerable economic unease.

He said: "The only outcome is that (the riots) damage prospects of bringing more jobs here, damage the prospects of young people who want to get into work and damage the prospects of us having prosperity in Northern Ireland."