A new foot-passenger only ferry service linking Nanaimo and Vancouver won't set sail this summer.

In a Facebook post, Island Ferry Services said it is continuing to work on launching its harbour-to-harbour catamaran service that it originally planned to launch in July.

The company said it is in the midst of negotiating with TransLink, completing an "unexpected" environmental assessment and receiving approval to modify infrastructure at the Nanaimo Port Authority.

"Admittedly, this is a very long update and the news will be disappointing to many. Including us," Island Ferry Services wrote.

"This is a complex, expensive undertaking with many moving parts (some of which have been most unexpected), yet we are working diligently through the regulatory processes to 'keep those parts moving in the same direction,' and get this service underway."

The company said it needs to complete several other tasks before starting the service, but hasn't set a specific time for when it might open.