NI Secretary Peter Hain has said anti-terror intelligence gathering in Northern Ireland must be brought in line with the rest of the UK.
MI5 is to take the lead role in NI anti-terror work
Mr Hain told MPs the province needed protection from "modern terrorism" and MI5 was best placed to carry it out.
The measure is included in the Miscellaneous Provisions Bill, which paves the way for policing and justice to be devolved to the assembly.
It received an unopposed second reading in the House of Commons on Monday.
Mr Hain said the international nature of terrorism meant the security services (MI5) should now take primacy over the police force.
"Modern terrorism is an international phenomenon which Northern Ireland needs to be protected from," he told MPs.
The police would retain control over "operational" matters, but he added "we cannot address national security on a regional basis".
The change reflected the increasing "normalisation of life, security and politics" in Northern Ireland.
During the debate, some MPs said the security services were already "over-stretched" and adding Northern Ireland to their remit would only make things worse.
But Mr Hain said the question of resources was different to ensuring a consensus existed on the principle of the change, which he believed existed.
Mr Hain said 2006 was a "crucial year" for Northern Ireland and the legislation is "preparing Northern Ireland for the many varied challenges that lie ahead".
"There should be no legislative obstacle in the way of devolution," he said.
The wide-ranging bill also covers electoral and energy reform.