Speaking after Liverpool's 2-0 home win against Watford on Sunday, Klopp said he had made a mistake.
"Last time I spoke about Basel, I spoke like a supporter and I invited all Liverpool fans to Basel," the German told reporters.
"That was not too smart, to be honest. Basel is a nice city but it is not ready for us and it was my mistake. Please only people with tickets go there because everything else will be chaos and we don't want this.
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"It is really, really, really necessary that you now listen. Most of the time you can ignore what I say but now it is important."
Liverpool's last European final was in the Champions League against AC Milan in Athens' Olympic Stadium in 2007.
That match witnessed scenes of chaos after thousands of Liverpool supporters who had bought tickets were denied entry after being informed that the stadium was full.
Media reports at the time said many fans had entered the stadium with fake tickets, and the situation outside the ground soon turned disorderly, with Greek police using tear gas and batons on disgruntled supporters.
A UEFA report in the wake of the game branded Liverpool supporters "the worst fans in Europe", while UEFA itself was subsequently criticised for poor ticketing procedures and lack of adequate crowd control.
(Reporting by Simon Jennings in Bengaluru; Editing by John O'Brien)
