Koeman is currently focusing on the Netherlands' upcoming Euro 2020 qualification matches against Northern Ireland and Estonia.
The Dutch currently sit top of their group, on the equal points with second-placed Germany.
The Netherland's first game is crucial, as the Northern Irish sit just three points behind them in third place and only the top two teams qualify.
"[Joining Barcelona] is a possibility, but only after Euro 2020," Koeman said (as per Marca).
"I don't know if I'll keep [talking about the Barcelona job] in the future because it's a bit strange to speak about the possibility of going to the club while you're the Netherlands coach."
Despite being top of the La Liga table, Barça are only ahead of bitter rivals Real Madrid on goal difference and one bad result away from falling out of the Champions League places.
Hoogma also spoke of a release clause in the Netherlands manager's contract that becomes active after Euro 2020.
"Agreements were reached in this regard [for Koeman to leave], but [teams] would have to pay to do so," he said in October.
Barcelona would have to pay the KNVB a fixed compensation fee if they wanted to secure Koeman's services after next summer's tournament.
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