The Fine Gael leader has accused Sinn Féin of "juvenile behaviour" in its opposition to a Gaelic football match between members of the Oireachtas politicians and police from the North.
Mr Enda Kenny was responding to Sinn Féin TD Mr Martin Ferris's call for next Tuesday's game in Dublin to be called off.
Mr Ferris cited alleged collusion between the Royal Ulster Constabulary and loyalist paramilitaries as a reason to cancel the game.
He also said members of the Police Service of Northern Ireland, which replaced the RUC, and the British army were still harassing members and supporters of the Gaelic Athletic Association.
During a visit to Co Donegal today, however, Mr Kenny insisted Sinn Féin needed to take its responsibilities to the peace process seriously.
"It is high time that Sinn Féin . . . played their part in creating an inclusive policing service in Northern Ireland. The party is out of step with all other political parties in refusing to join the Policing Board.
"They are out of step with the main churches. They are even out of step with the GAA, which has proactively removed its former ban on the participation of members of the Northern security services," Mr Kenny said.
He added: "Sinn Féin would do better to sign up for the policing arrangements than engaging in unwarranted attacks on a sporting event designed to help foster north-south relations".
In November 2001, the GAA ended its controversial ban on members of the security forces playing Gaelic football and hurling. A PSNI Gaelic football team played its first game last October against the Garda.
Next week's Gaelic football match has been organised by Mr Jimmy Deenihan, a Fine Gael politician who captained the All-Ireland Championship-winning Kerry team in 1981.
PA