The Tánaiste says Gardaí are working closely with Police in the North after a series of bomb alerts in Belfast.
Last night a firebomb was left in a sports store in the Cornmarket area of the city, just a few hundred yards from where a car bomb exploded on Friday.
The Justice Minister and Garda Commissioner are due to meet their northern counterparts later to discuss the situation.
Tánaiste Eamon Gilmore says the Gardaí are offering the PSNI their full support.
"This type of activity has got to stop," he said. "There's a very high level of cooperation between the PSNI and the Garda Síochína on this."