The parliamentary watchdog has launched an investigation into the Democratic Unionist Party (DUP) MP Gregory Campbell over potential spending breaches.

The Independent Parliamentary Standards Authority (IPSA) said it will determine whether Campbell has been “paid an amount under the Scheme of MPs Staffing and Business Costs, external that should not have been allowed”.

No further information will be published until the investigation has concluded.

A DUP spokesperson said: “Gregory Campbell has spent twenty-five years working for the people of East Londonderry.

“He is one of the most active constituency MPs and consistently has one of the lowest costs of NI MPs.”

The party claim this is a “politicised complaint” made against Campbell about information cards and leaflets he personally distributes throughout his constituency weekly.

“Mr Campbell had already provided information about this matter and will fully cooperate with the investigation.”

They added that while the process is ongoing, he “will make no further comment”.