Liverpool will ban any supporters found selling Champions League final tickets.
Around 17,000 fans are set to attend the Reds’ second appearance in the showpiece of Europe’s elite club competition in Madrid on June 1.
A number of the club’s UEFA allocation were made available through a ballot on Thursday but some appeared on ticket resale sites within hours for up to £35,000.
In efforts to discourage fans paying high prices for the game with Tottenham at the Estadio Metropolitano, Anfield chiefs have threatened tough sanctions.
And they include a potential ban from attending home games for the foreseeable future.
“Liverpool FC has issued advice to supporters on the sale and purchase of Champions League final tickets via secondary and unofficial ticketing sites,” read a club statement.
“Fans are warned that buying tickets via unofficial online sources does not guarantee tickets are genuine or that they will actually receive them.
“As part of its commitment to tackle ticket touting, the club has created a test purchase programme to help protect supporters from purchasing via unauthorised ticketing sites.
“The programme aims to identify and stop these sales.
“While selling or offering to sell tickets without the permission of the club is a criminal offence, LFC also intends to impose sanctions on any supporters found to be selling tickets through unofficial secondary ticketing sites.
“Sanctions could include ticket-buying suspensions and indefinite bans from Anfield.
“It could also mean that any tickets for the Champions League final in Madrid are invalid, and purchasers will be unable to gain access to Estadio Metropolitano.”