Liverpool chief executive Ian Ayre has voiced "major concerns" about the behaviour of Zenit St Petersburg supporters ahead of Thursday's Europa League clash in Russia.
A group of the Russian Premier League club's supporters published a manifesto late last year calling for all gay and non-white players to be banned from playing for them - although they subsequently issued a statement in an attempt to clarify the comments.
The manifesto, which declared that "black players are being imposed on Zenit almost by force", prompted defender Chris Samba - who has since moved on to QPR - to label the St Petersburg side's fans racist.
Manager Luciano Spalletti quickly distanced himself from the manifesto, but Ayre has written to both UEFA and to Zenit to voice his concerns.
Liverpool are set to include a number of black players in their squad for Thursday's match, and the chief executive has sought assurances that the Russian club will take action to prevent abuse.
He told Liverpool's website: "It's been a major concern for us, so I wrote to UEFA very recently expressing our concerns to them - and also to Zenit themselves. We await some responses in that regard.
"The most we can do is make our feelings clear ahead of the game, and hope that we get an adequate response and adequate support on the night. That's about the most we can do at this stage.
"I'm certainly hopeful that the right people will take the right action to ensure it's a game where we don't have that type of incident.
"We do plan to speak to the players about it. As with everything, the players have a lot to take on board around such a big game - so we're going to do that just ahead of the game.
"The most important thing for our players is that they remain professional throughout this. We certainly won't tolerate that type of attitude or any of those types of incidents from our team.
"So the important thing is that we let them know how we expect them to act if there is an incident.""
Ayre has indicated that Liverpool's players will not walk off the pitch if there is racial abuse directed at them on Thursday, instead suggesting that any action on the field will be left in the hands of Spanish referee Carlos Velasco Carballo.
Asked what the club would do if any of their players were racially abused, Ayre said: "We'll take the right action. The referee would be at the forefront of that if there's something on the pitch.
"Anything that happens off the pitch, then we'll work very closely with the authorities. Those authorities will be UEFA, who are sanctioning and hosting the match, and Zenit and ourselves.
"I'll be there at the game and I'll ensure that we do whatever we need to do to protect anything that happens to any of our players. We'll ensure that happens."