Dexter says he will likely release more details including a date as early as Tuesday.
He says the main focus of the meeting will be finding ways to co-operate with Ottawa as it updates its plans for the economy.
Dexter won't say whether Prime Minister Stephen Harper will attend, saying only that an invitation has been extended.
The meeting was first talked about during a gathering in Halifax last July of the Council of the Federation.
At the time, a spokesman for Harper said the prime minister wouldn't be attending the fall meeting.