National's leader is keeping tight lipped on a late-night talkback saga - reportedly involving a senior National Party figure

There are allegations board member Roger Bridge called Marcus Lush's show last Monday - under the name 'Merv.'

He told Marcus he lived in Manurewa and asked questions about Auckland Central candidate Nuwi Samarakone - who yesterday lost the candidacy battle to Emma Mellow.

Judith Collins says it's not something she approves of - but it's a party matter.

Newstalk ZB understands the person called from Bridge's phone.