Gardaí have already taken up security duties at Shannon ahead of a possible visit by US President Donald Trump next month.
Officers have been deployed to a road security box at the entrance to Shannon Airport monitoring traffic entering the airport on at 24-basis since yesterday.
While there has been no confirmation from Gardaí that the measure is directly linked with a possible visit by President Trump, sources have confirmed that it is.
It is expected that the presidential jet, Air Force One, and other accompanying aircraft will arrive in Shannon on June 5 with Mr Trump likely to stay at his family’s hotel and golf resort in Doonbeg for two nights.
It is not yet clear whether the president will be transported from Shannon Airport by helicopter or if he will travel by road. It is understood that a number of routes have already been investigated and chosen for what will be an extensive presidential cavalcade.
Similar measures put in place for the visit of President George W Bush in 2004 are expected to be implemented again and will involve hundreds of manhole covers and drains along the entire route of the Presidential cavalcade being inspected and welded shut.
The route from Shannon Airport to Doonbeg is however almost four times longer, at 60kms, than that taken by President Bush at the time.
Gardaí will also be posted along the entire route to the Trump property in Doonbeg including on every flyover and interchange along 22 kilometres of N19 dual-carriageway and M18 motorway.
It is also understood that more than 1,000 gardaí have been placed on standby for the massive security operation while personnel from all three arms of the Defence Forces are also likely to be deployed for the duration.
It is also known that as many as 30 US officials, including secret service agents, visited the Trump property earlier this month. It is expected that further advance parties will arrive over the coming days as the security operation is stepped up.