Ireland had not last night followed the example of countries such as Italy and declared a state of alert amid fears of retaliatory attacks.
Questioned by journalists yesterday, the Taoiseach Mr Ahern called on everyone to exercise "all reasonable care".
Mr Ahern said: "Hopefully it is not going to affect us."
A spokesman for the Department of Justice said the security services were taking all necessary precautions and the State's security situation was under continuous review. A spokesman for the Department said should the need arise, an instruction to heighten security would come from the recently established Office of Emergency Planning, which is based at the Department's headquarters at Infirmary Road.
Meanwhile, an Army spokesman said the State's security status had not changed.
"To be realistic about it you can only act on realistic threat assessment and there has been nothing passed to the defence forces yet to indicate any need for a change in status," he said.
However, a Garda spokesman said officers had been on a "heightened state of alert" since September 11th.
"In relation to recent world events An Garda S∅ochβna is on a heightened state of alert since September 11th, 2001 after the attacks on New York and Washington."
He said garda∅ were in regular contact with US counterparts and throughout the rest of the world about recent events.