The army has begun deploying up to 2,000 troops, as well as heavy armour, around Shannon Airport in preparation for the visit to Ireland of US President George W Bush.
An army spokesman said the level of threat to the President was currently regarded as being 'low' but a major security operation was necessary to ensure his safety.
An alliance of non-Governmental organisations earlier said protests against the visit would be completely peaceful.
The NGO Peace Alliance said the visit was merely a photo opportunity for Mr Bush to attract Irish and Catholic votes in the forthcoming US Presidential election.
The alliance has criticised President Mary McAleese for her decision to meet Mr Bush at the weekend.
A spokesman for group, Brendan Butler, said it was enough for the Taoiseach to welcome him, but for Ireland's President to join in his re-election campaign was offensive to the vast proportion of Irish people who opposed his visit.
Representatives of the Labour Party, the Green Party, Sinn Féin and the Socialist Party also attended this morning's news conference.
EU-US summit tomorrow
Mr Bush is due to arrive in Ireland tomorrow for this weekend's EU-US summit at Dromoland Castle in Co Clare.
He will leave for Ankara on Saturday before heading on to Istanbul.
Ahead of his visit to Ireland, Amnesty International has called on the Government to break the EU's silence on what it terms the ongoing breaches of human rights and humanitarian law by the US in its 'war on terror' and in Iraq.
However, speaking on RTÉ, the Minister for Arts, Sport and Tourism, John O'Donoghue, said it was not true that the EU had not voiced its criticism of Washington's Iraq policy.
Open letter from human rights group
The call by Amnesty International comes in an open letter released by the human rights group in advance of tomorrow's summit.
The letter states that it is the ideal time to confront Mr Bush with the strength of international opinion on the horrors of the detention centres in Iraq, Guantanamo Bay and Afghanistan.
'With clear evidence of torture by US forces and no limit on how high up the chain of command responsibility lies, the EU's silence has been shameful and deafening', the letter says.
While Amnesty acknowledges that the EU expressed its concerns about the mistreatment of prisoners in Baghdad's Abu Ghraib jail last May, it says the EU has not officially or forcefully taken up the matter with the US.
Open detention facilities, US urged
The letter asks the Government to call on Mr Bush to open the doors of its detention facilities to UN and other human rights monitors.
Commenting yesterday, the Tánaiste Mary Harney said that while the US was politically and economically important for Ireland, the Government would make it clear to Mr Bush that Ireland and the EU did not agree with him on many foreign-policy issues.
Helpline number
Meanwhile, gardaí have released a helpline number regarding the Bush visit for people travelling to and from Shannon this weekend.
The main dual carriageway from Shannon to Ennis will be closed for 24 hours from 3pm tomorrow afternoon and diversions will be in place.
The helpline number is 061-717814.
