An announcement by the Home Secretary that the threat from Northern Ireland-related terrorism has been downgraded from substantial to moderate, meaning an attack is possible but unlikely, "may be both premature and somewhat counter-productive", the DUP Parliamentary Group Leader has warned.
Nigel Dodds urged newly-appointed Northern Ireland Secretary Theresa Villiers to give an assurance that "there won't be any reduction in security or any complacency on the part of the security forces".
Ms Villiers replied that in both Great Britain and Northern Ireland the Government was focused on defeating terrorism and would "use all means at our disposal to do that".
Theresa May earlier said the threat level to Great Britain was being reduced, but the threat to Northern Ireland remains at severe, meaning an attack there is highly likely.
The threat from international terrorism also remains substantial, meaning an attack is a strong possibility, she added.
Speaking during Commons Northern Ireland questions on Wednesday, Mr Dodds said: "The Secretary of State will know that the announcement made this morning by the Home Secretary that the threat level from dissident republicans in the mainland has been reduced from substantial to moderate.
"Does she share the concern that many people have that such an announcement may be both premature and somewhat counter-productive and can she give an assurance to the House, given recent experience about intelligence level reports, that there won't be any reduction in security or any complacency on the part of the security forces."
Ms Villiers replied: "I can give him that assurance that we will continue to be vigilant in the face of the continuing threat in relation to Northern Ireland-related terrorism.
"He will appreciate that the change announced today as he says relates to Great Britain, the threat level in Northern Ireland remains at severe.
"In both Great Britain and Northern Ireland the Government is focused on defeating terrorism and we will use all means at our disposal to do that."