The airport boss criticised the all-Ireland body in a strongly-worded letter obtained by the BBC's The View programme
The head of Belfast International Airport has told Enda Kenny that Belfast should become "the gateway to Ireland".
Graham Keddie told the taoiseach (Irish prime minister) that Tourism Ireland needed to change its work in Northern Ireland.
The airport boss criticised the all-Ireland body in a strongly-worded letter obtained by the BBC's The View.
Tourism Ireland promotes Northern Ireland and Ireland abroad.
Brexit not an "à la carte"execise says Belfast International Airport's managing director Graham Keddie
Graham Keddie also told Mr Kenny that the Brexit vote was not an "a la carte" exercise.
He said different parts of the UK cannot remain in the EU and do what he termed "solo runs".
As Belfast International Airport's managing director, Mr Keddie was invited by the taoiseach to take part the All-Island Civic Dialogue on Brexit in Dublin earlier this month, but was unable to attend.
Mr Keddie said the changed economic times required a shift in emphasis.
Graham Keddie said a weaker pound made Northern Ireland more attractive to tourists from Great Britain and a strong euro made the Republic more expensive.
Graham Keddie says Tourism Ireland's work should be refocused north of the Border
"Just as Tourism Ireland aggressively marketed and promoted the Republic of Ireland through Dublin, we expect no less an effort now that the situation is reversed," he told Enda Kenny.
"Perhaps that is something you and your colleagues could impress on Tourism Ireland in the interests of fairness and equality."
Graham Keddie also said that Belfast needed to be a greater priority.
"Now for the first time we can say to an important market that they can use Belfast as the gateway to not only Northern Ireland, but the island as a whole," he wrote.
'Dublin focused agenda'
Mr Keddie's letter has been commended by North Antrim MP Ian Paisley, who this week raised the issue of tourism and travel in the House of Commons.
The DUP MP told The View: "I think it is very clear that the agenda of Tourism Ireland has been very much Dublin focused.
"Here we have an international airport operating in Northern Ireland and its CEO spelling out loud and clear that it wants a fair crack of the whip, it wants Tourism Ireland to do its job and to see Northern Ireland as the gateway into the island of Ireland - not Dublin airport."
Earlier this month, US airline United announced it was to stop flights between Belfast and New York, months after a £9m rescue deal.
Two thirds of the money, which was to be given to United over three years, was to come from the Northern Ireland Executive.
The flight is the only direct air link between Northern Ireland and the US.
The European Commission has said EU rules do not allow public authorities to grant a specific airline an "undue advantage".
SDLP MLA Sinead Bradley said it is unrealistic to suggest that Belfast International Airport could become the gateway to Ireland.
"We can only judge people on their past record," she said.
"We don't have to look too far back to see the saga that United Airlines and our only transatlantic flight that has been lost.
Sinead Bradley said it is unrealistic to suggest that Belfast International Airport could become the gateway to Ireland
"And then to make bold statements such as this does not really have much credibility that is unfortunate.
"I would love to see that would be the day but we do have thankfully Dublin International Airport and many of us have had to turn to Dublin as the only route to such places as America."
When contacted by The View, a spokesman for Belfast International Airport said he had nothing to add to Mr Keddie's letter, which he described as constructive and helpful.
A spokeswoman for Tourism Ireland told the BBC that next week in Belfast, Tourism Ireland would launch its 2017 plans to promote Northern Ireland in GB and elsewhere around the world.
Tourism Ireland continues to promote Northern Ireland in 23 markets around the world - building on the record growth we have seen in 2016.
Bringing more visitors here remains an island-wide objective.
This intervention by Graham Keddie may not be universally supported, but it illustrates the tensions that exist in a crucial all-island industry - a business that is looking for certainty in a post-Brexit world.
You can see the full story in The View on BBC One NI from 22:40 on Thursday
