Irish Police have begun to question all residents on routes to be travelled by Britain’s Queen Elizabeth when she visits next month.

Officers have been instructed to knock on every door and talk to every person who lives in the properties adjacent to the Queen’s routes.

Full details of the itinerary for the Queen’s visit were confirmed on Wednesday and police are leaving no stone unturned with their security arrangements.

Residents along the routes will be subjected to an informal interview when their names, previous addresses and telephone numbers will be recorded.

Police have already started to question residents on Dublin’s North Quays and Thomas Street ahead of the visit to the nearby Guinness Storehouse.

Householders already interviewed by the police have been told that all notes will be destroyed after the Royal visit, the first by an English monarch in a hundred years and the first ever to the Republic.

The massive security operation for the visits of the Queen and US President Barack Obama could cost the Irish government over $30million.

A spokesman for the Department of Justice told the Irish Independent that it has yet to reach a final figure on the costs involved.

“While the financial requirements will undoubtedly be significant, the safety of the Queen and the President will be the paramount considerations involved for the police and the State,” said the spokesman.

Buckingham Palace has now confirmed the fill itinerary for Queen Elizabeth’s historic visit but has warned that it is subject to last minute change on security grounds.

Confirmed are visits to Aras an Uachtarain, Croke Park, the Garden of Remembrance and Trinity College on May 17th, the date of her arrival, but no timings have been revealed.

The Queen will also visit the National Stud in Kildare, the Rock of Cashel in Tipperary and the English Market and Tyndall Institute in Cork.