The Electoral Commission is investigating money paid by Mid and East Antrim Council to sponsor a table at a constituency dinner facilitated by DUP MP Ian Paisley.
The event took place at the Tullyglass Hotel in Ballymena last year.
Environment Secretary Michael Gove was the guest speaker at the event.
In a statement, the commission described the money paid as a “donation from Mid and East Antrim Council to Ian Paisley MP” the BBC reported.
Under electoral commission rules, councils are not considered “permissible donors” and money from such bodies must be returned.
But Ian Paisley insisted the council paid the hotel directly for the table.
In a statement the North Antrim MP said: “I can confirm that the Electoral Commission is continuing its investigation into Mid and East Antrim purchase of a table at my constituency dinner last year. I look forward to them concluding this matter soon,” he added.
Mid and East Antrim Council also denied paying any money to the DUP.
A council spokesperson said it received an invitation to a North Antrim Annual Business and Community dinner at the Tullyglass Hotel, hosted and facilitated by Ian Paisley MP, with speaker Michael Gove.
“Council made payment to the Tullyglass Hotel via electronic payment. No money was exchanged between Council and the DUP. Council will fully co-operate with any investigation,” they said.
Earlier this year the local government auditor said it too will be examining the payment.
In a statement, Audit Office officials said it would “specifically review that transaction as part of our audit procedures when we come to review the accounts”.