Demonstrations over the city council's decision last month to restrict the number of days the British flag is flown have resulted in more than 1,000 arrests and the injury of dozens of police officers, The Guardian reported.
Theresa Villiers, Northern Ireland secretary, said the province is being "held to ransom by protesters" and has called for an end to all street demonstrations over the Union Jack.
Unionist politicians involved in trying to defuse the dispute hope that the reappearance of the Union Jack Wednesday to mark the Duchess of Cambridge's birthday will halt the protests.
However, loyalists told the Guardian further protests are planned for the end of the week, including a demonstration outside the Irish parliament in Dublin on Saturday.
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