Mr Talbot said police were continuing to appeal for sightings over marine radio and were asking all members of the public to keep an eye out for the launch.
He said there was no longer an active search underway, but it would be revived if there were any new leads on Mr Blair's likely whereabouts.
"The marine radio broadcasts are still continuing and we're still seeking information from people out on the ocean or members of the public who might be able to tell us what his intentions were," he said.
Mr Talbot said the search could be resumed if any information came in directing searchers to a particular area.
Anyone with information should call Blenheim police, phone 03 578 5279.